1991 (MCMXCI) was a common year starting on Tuesday (link will display full calendar) of the Gregorian calendar in the 20th century. It was the second year of the 1990s, and is usually considered the final year of the Cold War that had begun in the late 1940s. During the year, the Union of Soviet Socialist Republics collapsed into fifteen sovereign republics. A U.N.-authorized coalition force from thirty-four nations fought against Iraq, which had invaded Kuwait in the previous year, 1990. The conflict would be called the Gulf War. The year 1991 was the 1991st year of Anno Domini, the 991st year of the 2nd millennium, the 91st year of the 20th century and 2nd in the 1990s.

1991 (MCMXCI) var ett normalår som började en tisdag i den gregorianska kalendern.