The Commonwealth of Massachusetts is a northern state of the United States of America. It was one of the original 13 colonies. By the mid 1780s, Massachusetts had territorial claims in Maine and parts of what is now Michigan and Wisconsin. The state ceded the western territories to the U.S. government in 1785 and Maine seceded from Massachusetts in 1820 as part of the Missouri Compromise.

The Battle of Lexington on April 19, 1775 was the first battle of the American Revolutionary War.

South Boston, a predominantly Irish town, was the operating area of Irish American mob boss James "Whitey" Bulger, who eluded the FBI for 16 years until he was captured in 2011. Bulger inspired the character of Cally Lonegan.

On April 15, 2013, the Boston Marathon was bombed by two Chechen brothers, killing 3 and injuring 264 people. After killing a police officer the next day, one of the terrorists was killed and his younger brother was taken into custody.