Easthampton (ēst-hămp´tən), town (1990 pop. 15,537), Hampshire co., W Mass.; inc. 1809. It is primarily a manufacturing town with diversified light industry. Easthampton was settled as early as 1664. In the 1820s the town's textile industry was founded by Samuel Williston; a boys' preparatory school there (now part of the coeducational Williston Northampton School) was later named for him.