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Massachusetts Bay Colony was a 17th Century British settlement on the east coast of North America. It was established in 1628; its charter revoked in 1684; and it became part of the Dominion of New England in 1686. Massachusetts Bay Colony included parts of New England, centered around Boston and Salem. The Colony included parts of present-day Massachusetts, Rhode Island, Connecticut, New Hampshire, and Maine. She claimed land to the Pacific Ocean. Her modern successor is now the Commonwealth of Massachusetts, one of the fifty United States.
The Massachusetts Bay Company included investors in the Dorchester Company which had colonized 1623-1626 Cape Ann (northwest of Salem). That company went bankrupt, the colony was abandoned, and some of her settlers moved to what became Salem. By 1828 the Massachusetts Bay Company began further settlements around Salem and Boston. From 1630 to 1640 about 20,000 mostly Puritan colonists arrived from England and Barbados in what is now called the Great Migration.
The Plymouth colony was not a part of the Massachusetts Bay Colony. It was independent 1620 to 1691 before annexation by the Massachusetts Bay Colony in 1691.
The repressive nature of the religious government of the Massachusetts Bay Colony resulted in large scale emigration from the area to the west areas including but not limited to, Rhode Island, Connecticut, New Hampshire, Vermont, Maine and New York as well as western part of Massachusetts.