European immigrants particularly the Irish settled in Massachusetts because of early industrialization. As late as 1990 more than half of the population identified with at least one single ancestry group. As of 2000 the largest were the Irish (22.5% of the population), Italian (13.5%), English (11.4%), French (8%), Polish (5.1%), and Portuguese (4.4%).

Massachusetts has always had a black population, and personalities such as poet Phillis Wheatley and NAACP founder W.E.B. DuBois) to US cultural and public life were black. The state also had 428,729 Hispanics and Latinos in 2000, predominantly Puerto Rican and Dominican.

Greater Boston has a small, well-organized Chinatown. Statewide, there were 84,392 Chinese in 2000 (up from 47,245 in 1990), 33,962 Vietnamese (up from 13,101 in 1990), 19,696 Cambodians, 17,369 Koreans, and 10,539 Japanese. In 2000, the total Asian population was estimated at 238,124, and the Native American population (including Eskimos and Aleuts) totaled an estimated 15,015.