Alida Carroll of Maryland and Washington D.C. married John Marshall Brown, a Portland resident, in 1866. The couple met while Brown was recuperating after being wounded before the Battle of Petersburg during the Civil War. Brown returned to Maine about a year before the couple married. The two engaged in a long distance courtship, followed by a Portland wedding in December of 1866.

Alida was the daughter of William Thomas Carroll, a US Supreme Court clerk and his wife Sally (Sprigg) Carroll, a socially well-connected couple in the region. Her mother Sally Sprigg was the daughter of former Maryland governor Samuel Sprigg.