Short answers, pulled from the story.
George Halas (born the 2nd of February, 1895; died the 31st of October, 1983) was the founder and owner of the Chicago Bears and one of the co-founders of the National Football League. He attended the 1920 meeting in Canton, Ohio, that established the American Professional Football Association, which became the NFL in 1922, and was the last surviving participant of that founding meeting at the time of his death.
Halas won six NFL Championships as head coach, a record tied for the most all time, later matched by Green Bay's Curly Lambeau and New England's Bill Belichick. His championships came in 1921, 1933, 1940, 1941, 1946, and 1963.
Halas developed the T-formation with University of Chicago coach Clark Shaughnessy in the late 1930s, a system built on complex fakes, spins, and athletic versatility. In the 1940 NFL Championship Game, the Bears defeated the Washington Redskins 73-0, still the most lopsided margin of victory in NFL history, and every other team in the league immediately began trying to copy the system.
Halas was 72 years and 318 days old when he coached his final game in December 1967, making him the oldest head coach in NFL history at the time. He officially retired on the 27th of May, 1968. That record stood for over 50 years until Romeo Crennel became interim head coach of the Houston Texans in October 2020 at age 73 years and 115 days.
Halas played 12 games as an outfielder for the New York Yankees in 1919 before a hip injury ended his baseball career. He helped found the American Basketball League in 1925, the first professional basketball league in the United States, and owned the Chicago Bruins basketball team, which reached the World Professional Basketball Tournament finals in 1940 before losing to the Harlem Globetrotters 31-29.
Halas is entombed in St. Adalbert Catholic Cemetery in Niles, Illinois. The Pro Football Hall of Fame stands on a street named George Halas Drive, the NFC Championship Trophy bears his name, and from the 1984 season onward every Chicago Bears jersey carries the initials "GSH" on the upper left sleeve.