Cary was baptized in All Saints Parish, Bristol, England, on January 30, 1623. He was the son of a woolen draper, John Cary, and his second wife, Alice Hobson Cary. Both of his grandfathers had been mayors of Bristol, and as a member of a socially prominent and respected family he received a good education, the details of which are not known. The English Civil Wars divided the family, and Cary’s father suffered substantial losses. Perhaps as a consequence, Cary became involved in the tobacco trade and moved to Virginia, probably early in the 1640s and certainly no later than November 1645, when a mariner deposed that “one Miles Cary, a Bristoll man” then in Elizabeth City County, had failed to deliver 250 pounds of tobacco. Copies of Virginia records that refer to him often spell his given name as Myles or Mylles and his surname as Carey.
Cary initially resided in the Warwick County household of Thomas Taylor, who may have been a kinsman, and by about 1646 he had married Taylor’s daughter Anne. Before she died on an unrecorded date before June 1667, they had at least three daughters and four sons, including Henry Cary (ca. 1650–1720), who became a successful builder in Warwick County, Williamsburg, and Yorktown, and Miles Cary (d. 1709), who became an influential member of the House of Burgesses and surveyor general of Virginia. Opening a store and acting as an agent in various business transactions, Cary prospered and became a commissioner, or justice, of the peace by 1650. At that time he was still called Mr. Cary, but in 1654 when he patented 3,000 acres of land in the new county of Westmoreland he was identified as a major in the militia. When he renewed that patent three years later he was a lieutenant colonel, and by 1660 he was a colonel. He acquired more than 2,200 acres of land in Warwick County, some of which he inherited from Taylor. At the time of his death Cary also owned two lots in his native Bristol, a tract in Jamestown, and four plantations. His financial success exposed him to some criticism. In January 1650 a local woman denounced him as a “scabbed fisted knave,” likened him to a “pox,” and declared that if Cary could become a commissioner of the peace, “they will make Comrs of black doggs shortly.”
Cary became a collector of taxes in Warwick County in 1658 and was elected to the House of Burgesses the following year. He was present in the spring of 1660 when the General Assembly elected Sir William Berkeley governor, pending receipt of a new royal commission from Charles II, and was also a member of a committee of burgesses that later in that year drafted a petition to the king requesting forgiveness for submitting to Parliament and seeking the restoration of colonial privileges. In addition the committee asked that Virginia-born children be declared denizens of England.
Cary was a burgess again from 1661 to 1663 and on May 15, 1661, became escheator general of the colony, with responsibility for taking possession for the Crown of land that was forfeit for nonpayment of quitrents. He became a member of the governor’s Council on an unrecorded date before March 23, 1664. The scant surviving Council records from the period indicate that Cary participated in planning for the defense of the colony during the Second Anglo-Dutch War (1665–1667). One of his last recorded acts as a Council member was to sign a protest that the governor and Council sent to the king complaining that Maryland’s governor and Council refused to join in a voluntary reduction in the production of tobacco in order to raise its price.
On June 5, 1667, at the mouth of the James River four Dutch men-of-war captured an English frigate and approximately twenty merchant vessels. Four days later Cary drew up his will. According to family tradition he was shot and killed defending against the Dutch incursion, and it is possible that he had been wounded and then prepared the will, with its two codicils, while on his deathbed. Cary died on June 10, 1667, and was buried in a brick tomb on the grounds of his home at Windmill Point.