This work, based on a reading of seventy-three Michigan county histories, consists of an alphabetical list of more than 5,000 persons who moved west from Massachusetts to New York, Pennsylvania, Ohio, Michigan, and other states of the middle west. The list consists not only of Massachusetts pioneers in Michigan, but also many who, as relatives of the subjects of various biographical sketches, are merely referred to as having emigrated west from the Bay State. The purpose throughout is to supply name, date and town of birth, date of removal, and state in which the pioneer settled. Additional information given includes name of spouse, date of marriage, and the complete identification of all sources.