John Blair was born about 1687 in Scotland, the son of the Reverend Archibald Blair, a Scottish Episcopal clergyman. His family migrated to Virginia while John was young, joining relatives already established in the colony. His uncle, the Reverend James Blair, was commissary of the bishop of London in Virginia and the principal founder and first president of the College of William and Mary. This connection placed John within an unusually influential clerical and educational family. Blair grew up in Williamsburg during its development as the colonial capital. He was educated at the College of William and Mary, where Anglican theology, classics, mathematics, and preparation for government or the professions shaped elite students. Through his uncle he also observed the close relationship among church leadership, education, and politics in royal Virginia. Rather than enter the ministry, Blair pursued commerce and public administration. He became a merchant, acquiring the accounting, credit, and correspondence skills necessary in a tobacco-exporting colony. He married Mary Monro, with whom he established a large family. Their son John Blair Jr. later became a Revolutionary judge and justice of the United States Supreme Court. Blair’s commercial success, family connections, and reputation led to local office. He served in Williamsburg government and entered the House of Burgesses before joining the governor’s Council. Plantation and mercantile wealth placed him within the slaveholding elite, and his public authority was inseparable from that social order. Before he became acting royal governor, Blair had been shaped by migration from Scotland, Anglican clerical kinship, one of the colony’s rare collegiate educations, mercantile practice, marriage, and life in the political center of Williamsburg. He belonged to an older generation than the famous revolutionaries, but his family and institutional work helped create the environment in which they were educated.