Although slavery in the United States is typically associated with the Caribbean and the Antebellum American South, enslaved people existed to a lesser extent in New England: historians estimate that between 1755 and 1764, the Massachusetts enslaved population was approximately 2.2 percent of the total population; the slave population was generally concentrated in the industrial and coastal towns. Unlike in the American South, enslaved people in Massachusetts had legal rights, including the ability to file legal suits in court.

The practice of slavery in Massachusetts was ended gradually through case law. As an institution, it died out in the late 18th century through judicial actions litigated on behalf of slaves seeking manumission. Unlike some other jurisdictions, enslaved people in Massachusetts occupied a dual legal status of being both property and persons before the law, which entitled them to file legal suits in court. Prominent Massachusetts lawyer Benjamin Kent represented slaves in court against their masters as early as 1752. He won the first freedom suit in the British American colonies in 1766.Adams' Minutes of the Argument: Essex Superior Court, Salem, November 1766Legal Papers of John Adams, volume 2Love of Freedom: Black Women in Colonial and Revolutionary New England By Catherine Adams, Elizabeth H. PleckThe Proceedings of the Cambridge Historical Society, Volume 40, 1964-1966 The post-revolutionary court cases, starting in 1781, heard arguments contending that slavery was a violation of Christian principles and also a violation of the constitution of the Commonwealth. During the years 1781 to 1783, in three related cases known today as "the Quock Walker case," the Supreme Judicial Court applied the principle of judicial review to effectively abolish slavery in 1783 by declaring it incompatible with the state Constitution that had just been adopted in 1780. This did not have the effect of immediately freeing all slaves, however. Rather, it signaled to slaveowners that their right to own slaves would no longer be legally protected, and without that surety, it was no longer profitable to keep slaves in the first place. Those who owned the slaves then generally chose to replace the enslavement with some other arrangement, either indentured servitude for a fixed term or conventional, paid employment.

As a result of this, Massachusetts was the only state to have zero slaves enumerated on the 1790 federal census. (By 1790, the Vermont Republic had also officially ended slavery, but it was not admitted as a state until 1791.) Maine, in the 1790 Census, also lists no enslaved people among its population but did not become a state until 1820 (it was part of Massachusetts until 1820).

A large threat to former slaves and freemen living in Massachusetts, however, was that posed by slave catchers, whose profession was to look for runaway slaves who had successfully fled from the South and sheltered in the North. Under American law at the time, these individuals were subject to detention and return to slavery in any jurisdiction that had not yet ended slavery. Many abuses were also committed in which even blacks who were freeborn in the North could be falsely accused of being runaway slaves and spirited away to a life of slavery, as in the infamous case of Solomon Northup, who was freeborn in New York and kidnapped into slavery in Louisiana.

This ongoing uncertainty impelled the abolition movement in the North because it meant that even blacks living in free states could never truly be free until slavery was definitively ended all across the United States. Massachusetts became a leading center for abolitionism in early 19th-century America, with individual activists such as William Lloyd Garrison and Frederick Douglass as well as organizations like the Boston Vigilance Committee dedicated to advancing the cause.

The political tensions caused by the collision between abolitionism and pro-slavery forces in the United States led directly to the American Civil War in 1861. After the war's end in 1865, the Thirteenth Amendment to the United States Constitution was ratified by the states, including Massachusetts, which legally abolished slavery in the United States and ended the threat of enslavement or re-enslavement once and for all. This was the final date when slavery was formally outlawed in Massachusetts, although it had been a moribund institution for decades prior to that time.

After the end of legal slavery, however, racial segregation continued in Massachusetts as a de jure legal requirement in various contexts until the mid-20th century.

History

Enslavement of indigenous peoples

The European enslavement of indigenous peoples in New England began with English sailors travelling though the region in the 16th and early 17th centuries, decades before the establishment of the Massachusetts Bay Colony.Newell, Brethren by Nature, 18-19. In 1605, James Rosier described in detail how he and his shipmates captured five Wabanaki men in what is today Maine: "it was as much as five or sixe of us could doe to get them into the light horseman. For they were strong and so naked as our best hold was by their long haire on their heads."Thrush, Indigenous London, 42. Rosier and his shipmates took the captives to London, where they apparently hoped to instruct them in English and extract knowledge of Wabanaki government that might give them an advantage against their European competitors in the race to establish colonies in North America. Nine years later, in 1614, English sea captain Thomas Hunt abducted twenty-four Native Americans during a voyage to New England with John Smith. Plymouth Governor William Bradford later recalled that Hunt's goal was "to sell them for slaves in Spaine." One of Hunt's captives, a man named Squanto, made his way from Spain to England, where he learnt English, returned to North America, and assisted the Plymouth colonists in 1621.Warren, New England Bound, 3-4.

Following the establishment of Plymouth Colony in 1620 and the Massachusetts Bay Colony in 1630, the colonists quickly incorporated the practice of enslaving indigenous people into the economic, social, and political fabric of New England. In the first decades of colonization, the primary mode of enslavement was the taking captives during war.Newell, Margaret, "Indian Slavery in Colonial New England" in Allan Gallay (ed.) Indian Slavery in Colonial America. Lincoln: University of Nebraska Press, 2009. pp. 33-66. This practice became especially prevalent during the Pequot War from 1636 to 1638. In the early days of the fighting, colonists brought Pequot captives from various small conflicts to the Massachusetts General Court, where they declared them officially enslaved. In an early example, the Court ordered in October 1636 that a Pequot person named Chausop "bee kept a slave for life to worke" within the colony.Newell, Brethren by Nature, 26. As the fighting escalated and the number of captives increased, however, the colonists began trading in enslaved Pequots on a much greater scale. They ceased to rely on the General Court and adopted a more ad hoc approach, selling captives into slavery without a legal declaration. Prior to 1641, no statutes guided this emerging trade in indigenous slaves. Instead, as historian Margaret Newell has argued, the colonists acted in self-interest and justified their practice after the fact, by referring to existing European notions of a just war (a theory later codified in the Body of Liberties).Newell, Brethren by Nature, 28-30. As noted by American historian Wendy Warren in her 2016 work New England Bound: Slavery and Colonization in Early America, "the movement of enslaved and captured people around the Atlantic world also was, by the seventeenth century, an accepted reality."Warren, New England Bound, 31-32.

The enslavement of the Pequots reached its apex in May 1637, when New England colonists and their Mohegan and Narragansett allies attacked and massacred hundreds of Pequot men, women, and children near the Mystic River. The surviving captives, mostly women and children, were enslaved and divided amongst the victors and spread throughout region. The colonial militia took many captives directly, having been promised slaves as a reward for fighting. This resulted in a scramble to claim the most promising captives. Israel Stoughton hinted at the grotesque process in a letter to John Winthrop, the Governor of Massachusetts, in 1637: "ther is one [Pequot]... that is the fairest and largest that I saw amongst them... it is my desire to have her for a servant.... Liftenant Davenport also desireth one, to witt a tall one that hath 3 strokes upon her stummach."Newell, Brethren by Nature, 35 Captives not taken by individual militiamen were brought to Boston, where colonial leaders used them as field laborers and household servants, or sold them to planters in Barbados and Bermuda.Newell, Brethren by Nature, 54-59Warren, New England Bound, 93-95.

The enslavement of indigenous people in Massachusetts slowed in the decades after the Pequot War, but it rose to new heights during the violence surrounding King Philip's War in the mid-1670s. As New England colonists mobilized militia forces against an indigenous coalition of Narragansett, Wampanoag, and Nipmuc communities, they returned to the now familiar tactic of capture and enslavement. According to historian Margaret Newell, the desire for captives formed a "central preoccupation" for the colonists, often leading to a further escalation of the conflict.Newell, Brethren by Nature, 133. On the indigenous side, the fear of enslavement and sale to sugar plantations in the Caribbean dissuaded participants from surrender and encouraged the weakened nations to continue fighting. Some young men told an interpreter near the end of the war in 1676 that they would be inclined to make peace, but they were confident they would be enslaved if they did: "why shall wee have peace to bee made slaves, & either be kild or sent away to sea to Barbadoes... Let us live as long as wee can & die like men, & not live to bee enslaved." Their fears proved well-founded. A few months later, in the fall of 1676, a ship named the Seaflower left Boston with 180 "heathen... men, women and children" who had been "sentenced & [condemned] to Perpetuall Servitude & slavery." As in the aftermath of the Pequot War, hundreds of captives—both combatants and non-combatants—were taken as slaves by the colonial militia, sold to Massachusetts households, or shipped abroad to pay the colonies' war debt.Lepore, The Name of War, 154-156.

The rate of indigenous slavery declined in Massachusetts as the violence of King Philip's War faded and the 18th century began, but the reliance on coerced labor did not end. While fewer Native Americans were formally enslaved via capture, colonial courts began sentencing indigenous residents in the colony to terms of involuntary servitude for alleged thefts, a failure to pay debts, or committing acts of violence.Newell, Brethren by Nature, 212-226. In the neighboring colony of Rhode Island, courts often seized indigenous children from mothers, who they deemed "disorderly", and offered them as indentured servants to colonists.Ruth Wallis Herndon, "Women as Symbols of Disorder in Early Rhode Island," in Women and the Colonial Gaze, ed. Tamara L. Hunt and Micheline R. Lessard (New York: New York University Press, 2002), 82-83. While these various indenture contracts were definite in theory, abuses were common, terms were long, and involuntary servants with terms over two years could be sold and exchanged around the region.Newell, Brethren by Nature, 227-228.

Importation of enslaved Africans