Alexander Campbell was an early leader in the Second Great Awakening of the religious movement that has been referred to as the Restoration Movement, or Stone-Campbell Movement. The Campbell wing of the movement was said to begin with his father Thomas Campbell's publication in 1809 in Washington County, Pennsylvania, of The Declaration and Address of the Christian Association of Washington.

In 1832 the group of reformers led by the Campbells (known as the "Disciples of Christ") merged with a similar group that began in Kentucky under the leadership of Barton W. Stone. Several American church groups trace their history to the Campbells' leadership, including the Churches of Christ, the Christian churches and churches of Christ, Evangelical Christian Church in Canada, and the Christian Church (Disciples of Christ).

Alexander Campbell is also the founder of Bethany College in Bethany, West Virginia. Alexander Campbell was born near Ballymena, in the parish of Broughshane, County Antrim, Ireland. His parents were Thomas Campbell and Jane Corneigle Campbell. Of Scots-Irish descent, he was educated at the University of Glasgow, where he was greatly influenced by Scottish Enlightenment philosophy. He was also influenced by the English philosopher John Locke. At age 21, Alexander emigrated to the United States with his mother and siblings from Scotland, to join his father Thomas, who had emigrated there in 1807. They sailed from Scotland on the Latonia on August 3, 1809 and landed in New York on September 29th, then traveled overland to Philadelphia. Alexander was ordained by the Brush Run Church on January 1, 1812.