The 1961 major league baseball season began on April 10, 1961. The regular season ended on October 1, with the Cincinnati Reds and New York Yankees as the regular season champions of the National League and American League, respectively. The postseason began with Game 1 of the 58th World Series on October 4 and ended with Game 5 on October 9. In the second iteration of this World Series matchup, the Yankees defeated the Reds, four games to one, capturing their 19th championship in franchise history, since their previous in 1958. The season is best known for Yankee teammates Roger Maris' and Mickey Mantle's pursuit of Babe Ruth's prestigious 34-year-old single-season home run record of 60. Maris ultimately broke the record when he hit his 61st home run on the final day of the regular season, while Mantle was forced out of the lineup in late September due to a hip infection and finished with 54 home runs. Going into the season, the defending World Series champions were the Pittsburgh Pirates from the 1960 season.
For the third year, there were two separate All-Star Games played. The first, the 30th Major League Baseball All-Star Game, was held on July 11 at Candlestick Park in San Francisco, California, home of the San Francisco Giants. The National League won, 5–4. The second, the 31st Major League Baseball All-Star Game, was held on July 31 at Fenway Park in Boston, Massachusetts, home of the Boston Red Sox. The game ended in a 1–1 tie, due to a rainout following the end of the ninth inning.