The site on which you are standing was originally settled by Franciscan missionaries in 1588. For 175 years, the Convento de San Francisco served as headquarters for the men who labored on behalf of the Spanish king to bring the Catholic faith to the Native Americans who inhabited "la Florida". Following Governor James Moore's siege of St. Augustine in 1702, the destroyed buildings of the mission were reconstructed using coquina taken from the king's quarry on Anastasia Island. In 1763, the British took possession of Florida and designated St. Augustine as capital of the colony of East Florida.
A decision was made by the military authorities to occupy the former Franciscan mission and convert the chapel originally constructed in the 1730s and 1740s into a barracks. The friary where the missionaries lived was also renovated, with fire places added to the enlarged living quarters. When the Spanish returned to St. Augustine in 1783, the Franciscans initially reoccupied the site, but were soon replaced by the soldiers of the Spanish garrison. In 1821, Florida was ceded to the United States, and the U. S. Army took possession of the military post. It remained a Federal facility until 1907, when the Florida National Guard moved its headquarters from Tallahassee to St. Francis Barracks.