The Boston Red Sox are a professional baseball team based in Boston, Massachusetts, and a member of Major League Baseball’s American League Eastern Division. Founded in 1901 as one of the American League's eight charter franchises, the Red Sox's home ballpark has been Fenway Park since 1912. The "Red Sox" name was chosen by the team owner, John I. Taylor, around 1908, following previous Boston teams that had been known as the "Red Stockings". They have played in eleven World Series, winning seven.

Boston was a dominant team in the new league, defeating the Pittsburgh Pirates in the first World Series in 1903 and winning four more championships by 1918. However, they then went into one of the longest championship droughts in baseball history, called by some the "Curse of the Bambino" after its alleged beginning with the Red Sox's sale of Babe Ruth to the rival Yankees two years after their world championship in 1918, an 86-year wait before the team's sixth World Championship in 2004. However, the team's history during that period was hardly one of futility, but was rather punctuated with some of the most memorable moments in World Series history, including Enos Slaughter's "mad dash" in 1946, the "Impossible Dream" of 1967, Carlton Fisk's home run in 1975, and Bill Buckner's error in 1986. Red Sox history has also been marked by the team's intense rivalry with the New York Yankees, arguably the fiercest and most historic in North American professional sports. Since 2003, the Red Sox have been perennial playoff contenders and have won two World Series, emerging as one of the most successful MLB teams of the last decade.

Boston (pronounced /ˈbɒstən/ or locally /ˈbɔstən/ ( listen)) is the capital of and largest city in Massachusetts, and is one of the oldest cities in the United States. The largest city in New England, Boston is regarded as the unofficial "Capital of New England" for its economic and cultural impact on the entire New England region. The city proper, covering only 48.43 square miles, had a population of 617,594 according to the 2010 U.S. Census. Boston is also the anchor of a substantially larger metropolitan area called Greater Boston, home to 4.5 million people and the tenth-largest metropolitan area in the country. Greater Boston as a commuting region is home to 7.6 million people, making it the fifth-largest Combined Statistical Area in the United States.

In 1630, Puritan colonists from England founded the city on the Shawmut Peninsula. During the late 18th century, Boston was the location of several major events during the American Revolution, including the Boston Massacre and the Boston Tea Party. Several early battles of the American Revolution, such as the Battle of Bunker Hill and the Siege of Boston, occurred within the city and surrounding areas. Through land reclamation and municipal annexation, Boston has expanded beyond the peninsula. After American independence was attained Boston became a major shipping port and manufacturing center, and its rich history now helps attract many tourists, with Faneuil Hall alone attracting over 20 million every year. The city was the site of several firsts, including America's first public school, Boston Latin School (1635), and the first subway system in the United States (1897).