The Red Sox have defeated the following teams in the world series...

1903- The Red Sox defeated the Pittspurgh Pirates

1912-The Red Sox defeated the New York Giants (not in the major league today)

1915-The Red Sox defeated the Philidalphia Phillies

1916-The Red Sox defeated the Brooklyn Robbin (became the Brooklyn Dodgers then then the Los Angeles Dodgers)

1918-The Red Sox defeated the Chicago Cubs

2004-The Red Sox defeated the St. Louis Cardinals

2007-The Red Sox defeated the Colorado Rockies