Springfield is a city in the state of Massachusetts, United States, and the seat of Hampden County. Springfield sits on the eastern bank of the Connecticut River near its confluence with three rivers: the western Westfield River, the eastern Chicopee River, and the eastern Mill River.
As of the 2010 Census, the city's population was 153,060. As of 2018, the estimated population was 155,032, making it the third-largest city in Massachusetts, the fourth-most populous city in New England after Boston, Worcester, and Providence, and the 12th-most populous in the Northeastern United States. Metropolitan Springfield, as one of two metropolitan areas in Massachusetts (the other being Greater Boston), had a population of 692,942 as of 2010. The first Springfield in the New World, during the American Revolution, George Washington designated it as the site of the Springfield Armory for its central location, subsequently the site of Shays' Rebellion. The city would also play a pivotal role in the Civil War, as a major stop on the Underground Railroad and home of abolitionist John Brown, best known for his raid on Harpers Ferry, and for the Armory's manufacture of the famed "Springfield rifles" used ubiquitously by Union troops. Closing during the Johnson administration, today the national park historic site features the largest collection of historic American firearms in the world.