Anthony Allaire was born in Cincinnati, Ohio, on February 17, 1829. Allaire came from a prominent military family; his maternal grandfather served in the French and Indian and American Revolutionary Wars while his father was a veteran of the War of 1812 and the Mexican-American War. His uncle, Colonel John Lamb, had been wounded while fighting alongside General Richard Montgomery at the Battle of Quebec. Allaire was brought to New York City at an early age and, around 1848, he became a drillmaster for one of the many target companies existing in the city at the time.