Also known as the Knights Hospitaller, or simply the Hospitallers, the Order can originally trace its roots back as an offshoot of a Benedictine hospital established by Italian merchants in 1023 CE, after receiving permission from the Caliph Ali az-Zahir of Egypt to rebuild on the site of the Saint John the Baptist monastery destroyed almost twenty years earlier. Their mandate encompassed caring for the poor, sick, and injured faithful who made the pilgrimage to Jerusalem.
After the Western Christian conquest of Jerusalem in 1099 during the First Crusade, the organization took on the militaristic characteristics we’re more familiar with today, officially being charged under its own charter in 1113 by Pope Paschal II with the care and defence of the Holy Land; becoming one of the most powerful Christian groups in the region. By the middle of the twelfth century the Order was firmly divided into two branches: the military arm, and their monastic root that continued tending to the sick and injured.
However the conquest of the Holy Land by Islamic forces in 1291 would mean the expulsion of the Knights Hospitallers from Jerusalem, and a twenty-year search for a new home. And after two years of campaigning this search would come to an end with the surrender of Rhodes. Establishing their headquarters here, this victory was the first step toward further militarization of the Order as they would go on to fight off numerous raids by Barbary pirates. Despite these growing confrontations, they would continue to see good fortune as the dissolution of the Knights Templar in 1312 saw the majority of their property awarded to the Knights Hospitaller.
These holdings in turn would spread their influence east to England and north to Germany with the Order, also known as the Knights of Rhodes by this point, establishing eight chapters to oversee their new acquisitions.
Despite prior attempts by the Ottomans to root the Hospitallers out, even after making them a target with the defeat of the Byzantine Empire after the capture of Constantinople in 1453, the Order would continue to hold Rhodes against invasion until 1522 when the Knights would finally lose to Sultan Suleiman the Magnificent and his force of some two hundred thousand men. After the six-month siege ended the survivors were permitted to withdraw to Sicily, having earned the respect of Christian and Muslim alike for their valiant defense.