Fort Frederik was constructed in the mid-18th century by the Danish government to protect its interests in the Caribbean and to defend the western end of Saint Croix against incursion from other European powers. Fort Frederik was the focal point of two important events that led to the dissolution of the slave-based economy of the Virgin Islands. In 1848, Emancipation Revolt ended slavery in the Danish West Indies, but inaugurated a 30-year period of serfdom based on contract labor that ensured continuing control by plantation owners. Then in 1878, escalating tensions erupted into the Labor Riot and Fireburn, which ended the contract labor system. -NPS