The Knights Hospitaller was a religious military order of the Roman Catholic Church that began as a hospital founded in Jerusalem in 1080 to provide care for pilgrims to the Holy Land. After the First Crusade, Jerusalem came under the rule of western European powers, and the knights were charged with the care and defense of the region. Following the loss of the Holy Land by Christian forces, the Order operated from Rhodes, over which it was sovereign, and later from Malta where it administered a vassal state under the Spanish viceroy of Sicily. When Napoleon captured Malta in 1798 the knights ceased to be associated with any one place. This has given rise to successors that still exist today.