In 1820, Princeton students engaged in a game called 'ballown', which was a precursor to modern American football.

According to legend, William Webb Ellis picked up the ball and ran with it during a school football match in 1823, creating a new style of play where running with the ball predominated instead of kicking. This event is considered significant in the evolution of football.

In 1827, Harvard started the tradition of 'Bloody Monday', where freshman and sophomore classes would participate in a mass ballgame, showcasing the violent nature of early American football.

In 1860, Harvard's tradition known as 'Bloody Monday' involving a mass ballgame between freshman and sophomore classes was banned by town police and college authorities. This led to protests and mourning by students, marking a shift in the early history of American football.

Following Yale's lead, Harvard also banned the play of all forms of football in 1861, marking a turning point in the regulation of violent mob-style games in early American sports.

In 1862, the Oneida Football Club was formed, making it the oldest known football club in the United States. Consisting of graduates from Boston's elite preparatory schools, the team played from 1862 to 1865, contributing to the early development of American football.

American football started to diverge from rugby with rule changes instituted by Walter Camp, including the introduction of the line of scrimmage and down-and-distance rules.

The first American football game was played in 1869 between Rudgers and Princeton. The game had different rules compared to modern football, with a round ball and 25 players on each team. Players were not allowed to pick up or carry the ball, resembling a mix of Rugby and Soccer.

Rutgers played Columbia in the first intercollegiate football game in the state of New York, resulting in the first scoreless tie in the history of American football.

In 1873, Princeton and Rudgers came together to establish a standard set of rules for American football. The field dimensions were set to 122m x 76m, and the number of players per team was reduced from 25 to 20.

Representatives from Yale, Columbia, Princeton, and Rutgers met in New York City to codify the first set of intercollegiate football rules, standardizing the game that had previously varied between schools.

Visiting athletes from McGill University introduce Harvard athletes to a rugby-like game that becomes the basis of American football. The game is later introduced to Yale, and Walter Camp, a student at Yale, helps to standardize the rules of the game.

In 1875, Harvard athlete Nathaniel Curtis challenged Yale to a rugby-style game, leading to the adoption of rugby rules and the transition from association football to rugby at Yale.

Harvard and Yale played each other for the first time under the 'Concessionary Rules', with Harvard winning 4-0, marking the beginning of a historic rivalry in American football.

Walter Camp, known as the 'Father of American Football', made significant contributions to the development of the sport by proposing rule changes that shaped the modern game.

Walter Camp, known as the father of American football, introduced significant rule changes in 1880. These changes included reducing the number of players on each team from 15 to 11 and inventing the 'Snap' to bring more organization to the game.

In 1881, a group of Princeton players devised a strategy known as the 'Block Game' where they would hold onto the ball without making any progress to maintain their undefeated record. This tactic prolonged matches by preventing the opposing team from gaining possession.

In 1882, a group of Princeton players implemented a stall tactic during football games by snapping the ball and holding onto it without making any progress, in order to preserve their undefeated records.

In 1883, Walter Camp revised the scoring rules, establishing four points for a touchdown, two points for kicks after touchdowns, two points for safeties, and five for field goals, which had a significant impact on the scoring dynamics of American football.

On October 25, 1884, Yale scored over 100 points and shut out Dartmouth, marking a historic moment in American football with a dominant performance.

In 1887, game time was set at two halves of 45 minutes each, and two paid officials—a referee and an umpire—were mandated for each game, marking a significant step towards standardizing the officiating and duration of American football matches.

USC fielded its first American football team in 1888, playing and winning their first game against the Alliance Athletic Club with a 16-0 victory.

In 1889, officials in American football were given whistles and stopwatches, enhancing their ability to manage and regulate the game more effectively.

In 1890, Amos Alonzo Stagg, a former star end at Yale, is hired as a football coach at Springfield College in Massachusetts. Two years later, he moves to the University of Chicago, where he becomes a great innovator in American football, playing a key role in the development of the forward pass and creating offensive formations like the T formation.

In 1891, the first Stanford football team was organized without an official head coach. Yale coach Walter Camp later coached Stanford for two years starting from 1894.

The oldest college football rivalry in the West, the Big Game between Stanford and California, began on March 19, 1892, with Stanford winning 14-10.

The Pittsburg Athletic Club signed one of its players to the first known pro-football contract, covering all of the club's games for the year.

In 1894, the Flying Wedge or 'V-trick formation', a complex blocking tactic in American football, was outlawed due to its contribution to serious injuries, highlighting the evolving safety concerns in the sport.

On October 26, 1895, in a game between Georgia and North Carolina, the first forward pass in football history occurred when North Carolina back Joel Whitaker threw the ball instead of punting, and George Stephens caught it.

On November 7, 1895, the first college football game in Oklahoma Territory took place, where the 'Oklahoma City Terrors' defeated the Oklahoma Sooners 34-0. The Terrors were a mix of Methodist college students and high schoolers.

On November 9, 1895, John Heisman executed a hidden ball trick using quarterback Reynolds Tichenor to score Auburn's only touchdown in a game against Vanderbilt, which was the first game in the south decided by a field goal.

The Allegheny Athletic Association fielded the first completely professional football team for its abbreviated two-game season.

The Latrobe Athletic Association football team became the first team to play a full season with only professional players.

The touchdown points were changed from four to five.

The 1899 Sewanee Tigers football team is considered one of the greatest teams of early sport history. They went 12-0, outscoring opponents 322 to 10, with just 13 players known as the 'Iron Men'.

In May 1900, Fielding H. Yost was hired as the football coach at Stanford University. He later led the 1900 Stanford team to a successful season.

In 1901, Fielding H. Yost was hired as the head football coach for the Michigan Wolverines football team, leading them to become a dominant force in college football.

On November 21, 1902, the Philadelphia Athletics managed by Connie Mack won the first night football game ever played, defeating Kanaweola AC 39-0 at Elmira, New York.

The first professional indoor football game took place on December 29, 1902, as part of the World Series of Football organized by Tom O'Rouke. The Syracuse Athletic Club defeated the 'New York team' 5-0 in this historic event.

New York and Syracuse competed in the first indoor football game at New York's original Madison Square Garden, with Syracuse emerging victorious with a 6-0 win. This game marked a significant milestone in the history of American football.

In 1904, halfback Charles Follis made history by signing a contract with the Shelby Athletic Club in Ohio, becoming the first known black professional football player. His signing marked a significant milestone in the integration of professional football.

American football faced a crisis in 1905–06 due to its violent nature, leading to a surge in interest in rugby as an alternative football code.

In response to the violent nature of the game and the increasing number of deaths, Theodore Roosevelt almost banned football. This led to a meeting of 62 colleges and universities, resulting in the establishment of the Intercollegiate Athletic Association of the United States, later renamed the National Collegiate Athletic Association (NCAA).

In 1906, rules were modified to eliminate dirty plays in football. These changes aimed to improve player safety and sportsmanship within the game.

George (Peggy) Parratt of Massillon threw a completion to Dan (Bullet) Riley in a victory over a combined Benwood-Moundsville team, marking the first authenticated pass completion in a professional football game.

Field goal points dropped from four to three.

A touchdown was increased from five to six points.

In 1913, legendary athlete Jim Thorpe, known for his accomplishments in football and track, joined the Pine Village Pros in Indiana. Thorpe's involvement added prestige to the professional football scene.

In 1915, Jim Thorpe, a former Olympian and Carlisle Indian School standout, signed with the reformed Canton Bulldogs. Thorpe became a prominent figure in professional football and was present at the founding of the National Football League.

Canton, led by Jim Thorpe and Pete Calac, went undefeated, winning the Ohio League championship and being recognized as the professional football champion.

The Minnesota Vikings, a prominent NFL team, was founded in 1917, shaping the landscape of American football.

Under new ownership by Ralph Hay, Canton secured another Ohio League championship with the help of Jim Thorpe, Pete Calac, and Joe Guyon in the backfield.

In 1920, the legal forward pass was introduced in football along with other significant rule changes. The time of play was reduced to 60 minutes, field goals were reduced to 3 points, touchdowns were increased to 6 points, the field size was reduced to 91 meters, and two 9.1 meter end zones were created. Additionally, teams were given 4 downs instead of 3 to reach 9.1 meters.

The Akron Pros, Canton Bulldogs, Cleveland Indians, and Dayton Triangles represented at an organizational meeting in Canton, Ohio, resulted in the formation of the American Professional Football Conference.

On September 17, 1920, a second organizational meeting was held in Canton, where teams from four states - Ohio, Indiana, New York, and Illinois - came together to form the American Professional Football Association. Jim Thorpe was elected as the president of the league.

On September 26, the first game featuring an APFA team was played at Rock Island's Douglas Park, where the Independents defeated the St. Paul Ideals 48-0 in front of 800 spectators.

On October 3, the first game matching two APFA teams was held at Triangle Park, with Dayton defeating Columbus 14-0. This game marked the first touchdown scored in a game between Association teams.

After admitting the use of players with remaining college eligibility during the 1921 season, Clair and the Green Bay management decided to withdraw from the APFA. Curly Lambeau had to buy back the franchise with $50 of his own money due to rule violations.

The American Professional Football Association was reorganized in Akron, Ohio with Joe F. Carr elected as the new league president. The league saw a rapid increase in the number of teams due to a low entry barrier of a $100 membership fee.

The NFL President since 1921, Carr, passed away in Columbus on May 20.

After the death of NFL President Carr, Carl Storck was appointed as the acting president on May 25.

The American Professional Football Association changed its name to the National Football League.

The APFA was renamed to the National Football League on June 24, 1922. This change marked a significant milestone in the history of professional football.

Canton Bulldogs had their second consecutive undefeated season in 1923, finishing with an 11-0-1 record and winning the NFL title.

The Canton Bulldogs, later known as the Cleveland Bulldogs, won the NFL championship in 1923 and repeated the victory in 1924.

The NFL introduced a new position, the field judge, on July 28.

Providence hosted the first NFL game at night under floodlights against the Cardinals on November 3.

In November 1925, Harold (Red) Grange, an All-America halfback, signed a contract to play with the Chicago Bears. This signing was a major event in the history of the NFL, attracting a record crowd of 36,000 on Thanksgiving Day.

Ernie Nevers scored six rushing touchdowns and four extra points in a game against Red Grange's Bears, setting a record of 40 points that still stands as the NFL's oldest.

Pottsville scheduled a game against a team of former Notre Dame players at Shibe Park in Philadelphia, leading to a dispute with Frankford over territory and scheduling conflicts. Despite warnings from Carr, Pottsville proceeded to play the game on December 12, resulting in fines and suspension.

In 1926, the NFL grew to 22 teams, including the Brooklyn Lions, Hartford Blues, Los Angeles Buccaneers, and Louisville Colonels, with Racine Tornadoes re-entering. Each franchise's roster was limited to a maximum of 18 players.

At a special meeting in Cleveland on April 23, NFL President Joe Carr decided to secure the league's future by eliminating financially weaker teams and consolidating quality players onto a limited number of more successful teams.

On December 4, the Yellow Jackets scored in the final two minutes to defeat the Bears 7-6 and move ahead of them in the standings.

In 1928, the New York Giants emerged victorious in the NFL championship, securing the title with an impressive record of 10 shutouts in 13 games.

On July 27, 1929, Chris O'Brien sold the Chicago Cardinals to David Jones, marking a significant ownership change in the NFL.

Providence became the first NFL team to host a game at night under floodlights on November 3, 1929, against the Cardinals.

On November 28, 1929, Ernie Nevers of the Cardinals scored six rushing touchdowns and four extra points as they beat Red Grange's Bears 40-6, setting a record that remains the NFL's oldest.

The Giants defeated a team of former Notre Dame players coached by Knute Rockne 22-0 before 55,000 at the Polo Grounds on December 14, 1930. The proceeds went to the New York Unemployment Fund during the Great Depression, boosting the NFL's credibility.

On December 14, 1931, the Giants defeated a team of former Notre Dame players coached by Knute Rockne 22-0 at the Polo Grounds. The game's proceeds went to the New York Unemployment Fund during the Great Depression, boosting the NFL's credibility.

The NFL made significant changes from college football rules for the first time in 1932. They introduced innovations like hashmarks, goal posts on the goal lines, and legalized the forward pass from anywhere behind the line of scrimmage.

In July 1932, Marshall and Halas proposed to divide the NFL into two divisions, with the winners competing in an annual championship game.

On July 9, 1932, George Preston Marshall, Vincent Bendix, Jay O'Brien, and M. Dorland Doyle were awarded a franchise for Boston, leading to the formation of the new team named the Braves.

The Bears and the Spartans played the first-ever tie for first place in the NFL. The league arranged an additional regular-season game to determine the champion, which was moved indoors to Chicago Stadium due to extreme weather conditions.

The NFL made significant changes from college football rules for the first time, legalizing the forward pass from anywhere behind the line of scrimmage. This change marked a shift towards developing rules tailored to the NFL's needs and preferred style of play.

Marshall and Halas successfully proposed dividing the NFL into two divisions, with the winners meeting in an annual championship game. This structural change aimed to enhance competition and determine a clear league champion.

The Western Division champion Bears defeated the Eastern Division champion Giants 23-21 at Wrigley Field in the first NFL Championship Game scheduled before the season.

Professional football gained new prestige when the Bears were matched against the best college football players in the first Chicago College All-Star Game, which ended in a scoreless tie before 79,432 at Soldier Field.

In the championship game at the Polo Grounds, the Giants trailed the Bears 13-3 in the third quarter before changing to basketball shoes for better footing. The Giants won 30-13 in what has come to be known as the Sneakers Game.

The player waiver rule was adopted on December 10.

In the first NFL Championship Game of the season, the Western Division champion Bears defeated the Eastern Division champion Giants 23-21 at Wrigley Field.

The NFL adopted Bert Bell's proposal to hold an annual draft of college players, to begin in 1936, with teams selecting in an inverse order of finish. The inbounds line or hashmarks were moved nearer the center of the field.

The Lions defeated the Giants 26-7 in the NFL Championship Game.

The Eagles chose University of Chicago halfback and Heisman Trophy winner Jay Berwanger as the first player in the NFL draft. He was later traded to the Bears, but never played professional football.

Due to poor attendance, the NFL Championship Game was moved from Boston to the Polo Grounds in New York. Green Bay defeated the Redskins 21-6.

Homer Marshman was awarded a Cleveland franchise named the Rams on February 12.

On February 13, Marshall relocated the Redskins from Boston to Washington, D.C.

The Redskins signed TCU All-America tailback Sammy Baugh, who led them to a 28-21 victory over the Bears in the NFL Championship Game on December 12.

Rookie Byron (Whizzer) White of the Pittsburgh Pirates led the NFL in rushing. The New York Giants emerged victorious by defeating the Green Bay Packers 23-17 to clinch the NFL title on December 11.

In 1939, The New York Giants emerged victorious over the Pro All-Stars with a score of 13-10 in the inaugural Pro Bowl held at Wrigley Field in Los Angeles.

Carr, who had been serving as the NFL president since 1921, passed away in Columbus on May 20. Subsequently, Carl Storck was appointed as the acting president on May 25.

The first NFL game was televised by NBC, broadcasting the Brooklyn Dodgers-Philadelphia Eagles game from Ebbets Field to around 1,000 sets in New York.

In the period of 1940-1959, NFL attendance surpassed 1 million in a season for the first time, reaching 1,071,200.

In response to the player shortage caused by World War II, the Philadelphia Eagles and Pittsburgh Steelers merged to create the 'Phil-Pitt Steagles' team.

Green Bay defeated New York 27-0 in the NFL Championship Game held in Milwaukee. This victory marked a significant milestone as NFL attendance surpassed 1 million in a season for the first time, reaching 1,071,200.

The Card-Pitt team, a temporary merger during the 1944 NFL season, was divided back into the Chicago Cardinals and Pittsburgh Steelers for the 1945 season.

1946 marked the reintegration of the NFL as the Los Angeles Rams signed African American players Kenny Washington and Woody Strode. The year also saw the establishment of the All-America Football Conference (AAFC) as a competing league.

The NFL raised the roster limit for member teams from 33 to 35 players starting from the 1948 season.

The Boston Yanks ceased operations after the 1948 season, and a portion of the team was rebranded as the New York Bulldogs for 1949.

In 1950, the Eastern Division of the All-America Football Conference (AAFC) was renamed to the American Conference, while the Western Division became the National Conference. Teams like the San Francisco 49ers, Cleveland Browns, and the first Baltimore Colts joined the NFL from the defunct AAFC. The Baltimore Colts folded after the 1950 season, and the New York Bulldogs changed their name to the New York Yanks and moved to the National Conference.

In 1951, the NFL increased the maximum team roster size from 32 to 33 players for the season. However, the New York Yanks franchise was terminated after the 1951 season.

The Dallas Texans franchise was established in 1952 with the remains of the New York Yanks but folded after just one season. It is noted as the last NFL team to fold due to financial reasons.

In 1953, a second Baltimore Colts team was established from the remains of the Dallas Texans in the NFL.

Effective from the 1957 season, the NFL raised the roster limit from 33 to 35 players per team.

At the conclusion of the 1958 NFL season, the Baltimore Colts and the New York Giants played a historic game at Yankee Stadium, which went into sudden death overtime and became widely known as 'the Greatest Game Ever Played'. The final score was Colts 23, Giants 17.

In August 1959, the American Football League was organized in Chicago, with eight teams competing in its inaugural season in 1960. The league later merged with the NFL in 1969 after a successful run.

The Minnesota Vikings football team was founded in 1960 and has since become a prominent team in the NFL, with a strong fan base and a history of success.

In 1961, Gogolak revolutionized place kicking in American football. He introduced the soccer-style kicking technique, which became widely adopted in the sport.

The Pro Football Hall of Fame was officially dedicated in Canton, Ohio on September 7, 1963.

In 1964, the NFL raised the roster limit to 40 players, a number that remained unchanged until the conclusion of the 1973 season.

In 1966, the AFL and NFL agreed to a partial merger, leading to a common draft and the AFL-NFL World Championship game. This eventually evolved into the Super Bowl, marking a significant moment in professional football history.

The Super Bowl was established in 1967 following a merger agreement between the American Football League (AFL) and the National Football League (NFL), becoming one of the most iconic events in American sports.

Green Bay defeated Oakland 33-14 in Super Bowl II held in Miami on January 14, 1968. This game marked the first $3-million gate in professional football history.

In 1969, the New York Jets secured a 16-7 victory in the Super Bowl III, marking a significant turning point in the history of American football. The win had a profound impact on the sport and elevated Joe Namath to the status of a pop culture icon.

In 1970, the American Football League (AFL) and the National Football League (NFL) merged, leading to the creation of the Superbowl. This merger was a result of the intense rivalry between the two leagues, which ultimately benefited American football by pushing both leagues to improve.

In 1971, the Boston Patriots were renamed as the New England Patriots. Additionally, the size of the active player roster was increased from 40 to 47 players in 1974 before being reduced to 43 the next season.

The World Football League, formed in 1974, attracted NFL stars but faced financial issues leading to insolvency and shutdown in 1975.

In 1976, the Seattle Seahawks and Tampa Bay Buccaneers were enfranchised as new teams in the NFL.

In 1978, the size of the active roster in the NFL was increased from 43 to 45 players, a change that would last until the 1981 season.

In 1980, Pittsburgh defeated the Los Angeles Rams with a score of 31-19 in Super Bowl XIV at Pasadena, becoming the first team to win four Super Bowls.

In 1980, the NFL restructured its divisions, moving from 3 divisions with 26 teams to a setup with 32 teams and 4 conferences. This change also altered the playoff format, increasing the number of teams qualifying for the playoffs.

Arena football, designed to be played indoors, was invented in 1981 by Jim Foster, leading to the establishment of the Arena Football League in 1987 as the first major professional league for the sport.

In 1982, the Oakland Raiders relocated to Los Angeles, marking a significant shift in the team's location and fan base.

The Baltimore Colts moved to Indianapolis in 1984, a relocation that had a lasting impact on the team and the city.

In 1985, the size of the active roster in the NFL was reduced from 49 to 45 players, a change that would last until the end of the 1990 season.

The original USFL, which started as a spring league in 1983, moved its schedule to compete with the NFL in 1986 and filed an unsuccessful antitrust lawsuit, resulting in its folding.

In 1988, the St. Louis Cardinals relocated to Phoenix. This move marked a significant change in the team's location and fan base.

College football has maintained its prestigious status over the years and continues to be a major source of talent for the NFL. The NFL scouts players from college football teams, highlighting the ongoing importance of college football in the American football landscape.

In 1991, the NFL allowed teams to add a third 'emergency' quarterback to their active rosters. This rule was implemented to provide teams with more flexibility in case of quarterback injuries.

The NFL labor agreement established in 1993, renewed in 1998 and 2006, includes a hard salary cap and revenue sharing, promoting parity among teams and keeping player salaries low.

In 1994, the Phoenix Cardinals underwent a name change and became known as the Arizona Cardinals. This rebranding reflected the team's connection to the state of Arizona.

In 1995, the NFL expanded with the addition of two new teams - the Carolina Panthers and the Jacksonville Jaguars. This expansion aimed to increase the league's reach and competitiveness.

In 1996, the Cleveland Browns franchise was deactivated. This decision had significant implications for the team's history and fan base.

In 1998, the International Federation of American Football (IFAF) was established to coordinate international amateur competition, representing 45 associations and 23 million amateur athletes.

By 1999, the Super Bowl game was viewed by 127.5 million viewers, making it the sixth most-watched program in U.S. television history.

The original XFL was formed in 2001 as a joint venture between WWF and NBC, but it folded after one season due to declining fan interest.

In 2002, the NFL expanded to 32 teams, increased the playoff teams to 12, and restructured the 3 divisions into 4 conferences.

Jamaal Charles, the former NFL player, had a successful career as a running back for the Kansas City Chiefs and later for other teams in the NFL.

Joe Haden, the former NFL player, gained recognition for his exceptional skills as a defensive back while playing for the Cleveland Browns and later for other NFL teams.

In 2011, the active roster limit in the NFL was changed from 45 + 1 emergency quarterback to an undifferentiated 46 players, which remained in effect until the end of the 2019 campaign.

The St. Louis Rams returned to Los Angeles in 2016.

The Los Angeles Chargers won against the Dallas Cowboys with a score of 24-7.

The onset of the COVID-19 pandemic in 2020 introduced unprecedented challenges to the NFL, leading to adaptations such as limited audiences, rigorous testing protocols, and revised schedules.

The NFL started from humble beginnings and evolved into a multi-billion dollar industry. This event focuses on the league's modest origins and how it acquired the name NFL.

The game between @LAC and L resulted in a 24-17 victory for L.

The team played a match against the Green Bay Packers and won with a score of 17-13.

Forced fumbles are defensive plays in American football where the defensive player causes the ball to come loose from the offensive player's possession.