About a decade after the Civil War in America, college athletes began to blend a mix of soccer and European rugby. The game slowly evolved into what is now American rules football. By the late 1890s, there were a number of clubs paying small salaries to players.

This was a crude start to the professionalization of football. Over the next couple of decades, football teams across the Midwest became increasingly more organized. Many of these teams called Ohio home. As players started to realize their value, the organizational structure of pro football weakened.
 

The first of nearly a century's worth of historical moments happened on August 20, 1920. To improve organization and add stability to their leagues, team owners across four states met in Canton, Ohio. A month later, in September, owners named Jim Thorpe the first president of a 14 team professional league, the American Professional Football Association (APFA).

After two years of play, the league changed their name to the National Football League. With over 50 years of disorganization surrounding professional football, the sport had a governing body that would unify professional football across America.

During the first dozen seasons, the team with the best record during the regular schedule was crowned the league champion. Ties were broken by an orderly set of rules. It wasn't until 1932 that a problem arose.
 

League administrators decided the Chicago Bears and Portsmouth Spartans should play an additional game to decide the champion. This was the birth of the first NFL championship game. Prior to the 1935 season, there was no mandate for how many games a team had to play, only a minimum.
 

1960 marked a dramatic turning point for professional football in America. The NFL now had 40 years of success, but there were some who felt they wanted a part of what had become a lucrative enterprise.
 

An upstart group of wealthy men organized the American Football League, and for six years they stayed relatively competitive with the powerful NFL. They were so successful, that they began to take valuable college players from the NFL.

After six seasons of competing against one another, high-ranking executives from both the AFL and NFL sat down to discuss a common goal. Make football the most popular game in America.
 

On June 8 1966, the merger was finalized. For the next four years they continued to play as individual leagues, with a final game between league winners to decide the champion of pro football. The two leagues split those first four title games, the game that is now one of the most watched television events in the world; the Super Bowl.

Beginning with the 1966 season, two professional football leagues would play separate regular seasons, culminating in a final game to crown a champion of pro football. The NFL continued to be the dominant league early on. One of the original APFA members, the Green Bay Packers, won the first two title games. However, the landscape of pro football changed in 1969.
 

Led by an upstart and brash young quarterback named Joe Namath, the AFL's New York franchise shocked the world. The Jets beat the heavily favored Baltimore Colts in the title game, claiming the AFL's first championship. Kansas City mastermind Hank Stram would coach the Chiefs to the crown the following season, beating the Minnesota Vikings handily.
 

While these first four title games weren't yet called the Super Bowl, they ushered in what is known as pro football's Super Bowl Era. Having split the first two championships, the new league had proven a worthy compliment to the old guard of the NFL. In 1970, the merger was finalized.
 

The NFL split into two conferences, the American Football Conference and the National Football Conference. Three original members, the Pittsburgh Steelers, Cleveland Browns and Baltimore Colts shifted to the AFC to balance out the schedule.
 

It was during this 1970 season that an NFL legend Packers coach Vince Lombardi would die. As part of the merger in 1970, the final game between conference winners would be called the Super Bowl and the trophy awarded to the champion being the Vince Lombardi trophy.
 

Today, the Super Bowl is one of the most watched events in the world. It is sporting spectacle that transcends sports. Over the first 53 years, true parity has been exemplified between the two leagues that make up the Super Bowl era of the NFL.

The NFC has taken the trophy 27 times and the New England Patriots just won the AFC's 26th Super Bowl Championship. While in this current era, there have been new teams added and rule modifications that continue to change the game as it continues to grow increasingly more popular on a world stage.

Over these past 99 years, there have been hundreds of historical moments and monumental events in the NFL. Here are some most memorable highlights of the National Football League.

1935 – The NFL held its first college draft. The NFL draft is now a popular event for football fans.

1939 – After the 1939 season, the NFL held their first Pro Bowl at Wrigley Field in Chicago, Illinois.

1943 – Prior to the 1944 season, the NFL made wearing helmets mandatory.

1946 – The first major franchise move was permitted prior to the 1947 season, when the Cleveland Rams team moved west to Los Angeles.

1953 – First NFL president Jim Thorpe died on March 28.

1956 – Labor relations changed between owners and players with the formation of the NFL Players Association.

1960 – Kansas City businessman Lamar Hunt announces his decision to form a new professional league, the AFL.

1963 – The NFL designated the original founding city of Canton, Ohio as the place for the Pro Football Hall of Fame.

1966 – After an initial two league merger agreement, the Green Bay Packers beat Hunt's Kansas City franchise in the first league championship game between the AFL and NFL.

1970 – The league merger was finalized and with two conferences playing a separate regular season. The AFC and NFC would become the new NFL.

1970 – To coincide with the completed merger, the NFL and ABC Television entered into an agreement to broadcast a single game on Monday evenings. The agreement became a television legend known as Monday Night Football.

1972 – The Miami Dolphins beat the Washington Redskins by a touchdown, 14-7 to win the Super Bowl and become the only team in NFL history to go unbeaten for an entire season.

1976 – The first two franchise teams are added to the NFL, the Tampa Bay Buccaneers and Seattle Seahawks.

1977 – The Chicago Bears Walter Payton sets a new single-game mark by rushing for 275 yards against the Minnesota Vikings.

1980 – Pittsburgh beats the LA Rams in Super Bowl XIV to become the first team to win four titles.

1987 – The NFLPA called a month-long strike to contest what they felt were unfair labor practices by ownership.

2002 – Prior to the 2002 season, the NFL realigned into today's current division structure. The Houston Texans joined and the new 32 team league was broken down into 8 divisions of four teams each.

2002 – The Dallas Cowboys Emmitt Smith surpasses Walter Payton as the all-time rushing leader in NFL history.

2003 – The league launches its own television venture, the NFL Network.

2006 – The most prolific receiver in NFL history, San Francisco 49er Jerry Rice, retires.

2007 – In Super Bowl XLI, the New York Giants upend the New England, preventing the Patriots from becoming only the second undefeated team in league history.

2009 – Pittsburgh becomes the first team to capture six Super Bowl titles.

2017 – A national controversy is created when 49ers quarterback Colin Kaepernick kneels during the playing of the National Anthem.

2019 – New England beats the LA Rams 13-3 to match Pittsburgh for the most Super Bowl titles in NFL history.