"On my tombstone just write, 'The sorest loser that ever lived,'" he once said.
Weaver, 82, a member of baseball's Hall of Fame and the winningest manager in the franchise's history, died late Friday while on a baseball-themed cruise, said Monica Barlow, a team spokeswoman.
The cause apparently was a heart attack, the team said on its website.
His teams won 1,480 games and lost 1,060, and his winning percentage (.583) ranks ninth all-time and fifth among managers in the modern era who managed 10 years or more.
Five times, Baltimore won at least 100 games for Weaver, who was 5 feet 7 but stood mythically tall to his players.
"Having Earl gives us a four-game lead on everybody," pitcher Sammy Stewart once said.
The Orioles failed to post a winning record under Weaver only once, in 1986. His career was defined by an affinity for the three-run home run and a long-running, public feud with superstar pitcher Jim Palmer that both men jokingly played to whenever they were together.
Nicknamed "the Earl of Baltimore," Weaver was always a fan favorite. He repeatedly returned to Baltimore to take part in a series of statue unveilings at Oriole Park, including one dedicated to him in June.
Considered one of the game's great strategists, he was inducted into the Hall of Fame in 1996.
"Earl Weaver stands alone as the greatest manager in the history of the Orioles organization and one of the greatest in the history of baseball," Orioles managing partner Peter Angelos said Saturday in a statement.
As a manager, Weaver could be testy, but his closest friends also knew him to be sensitive and caring, though he seldom showed that side in public.
Weaver stood up for a couple of young players who would turn out to be among the greatest in the game.
He pressed to keep first baseman and future Hall of Famer Eddie Murray in the major leagues in 1977 and is credited with bucking convention to switch supposedly oversized Cal Ripken Jr. from third base to shortstop at the end of 1981. While playing for Weaver, Ripken began his record-breaking streak of playing in 2,632 consecutive games.
"His passion for the game and the fire with which he managed will always be remembered by baseball fans everywhere," Ripken said Saturday in a statement.
According to the Hall of Fame, Weaver pioneered the use of radar guns in professional baseball to track the speed of pitches, introducing the concept at spring training in 1975.
In some ways, he was a comic character. But Weaver had a hard edge that could rankle a player as easily as an umpire.
Weaver got under the skin of Bobby Grich in the early 1970s, yelling "home run or [go back to Triple-A] Rochester!" at the young second baseman as he went up to bat. Grich came back to the dugout and — after a loud verbal exchange — threw Weaver down steps that led to the clubhouse.
To Weaver's credit, Grich remained in the starting lineup for the next five seasons and established himself as one of the top power-hitting second basemen of his generation.