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The Knights Hospitaller, also known as the Order of Hospitallers or simply Hospitallers, were a group of men attached to a hospital in Jerusalem that was founded by Blessed Gerard around 1023 out of which two major Orders of Chivalry evolved, the Order of the Knights of St. Lazarus and the Order of the Knights of St. John, later to be known as the Sovereign Military Order of Malta.
The Hospitallers arose around the work of an Amalfitan hospital located at the Muristan site in Jerusalem, founded around 1023 to provide care for poor, sick or injured pilgrims to the Holy Land. After the Western Christian conquest of Jerusalem in 1099 during the First Crusade, the organisation became a religious and military order under its own charter, and was charged with the care and defence of the Holy Land. Following the conquest of the Holy Land by Islamic 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.
The Order was weakened by Napoleon's capture of Malta in 1798 and became dispersed throughout Europe. It regained strength during the early 19th century as it repurposed itself towards humanitarian and religious causes. The modern continuation of the mediaeval Order is the Roman Catholic Sovereign Military Order of Malta, headquartered in Rome;[1] allied Protestant orders are headquartered in the United Kingdom, Germany, the Netherlands and Sweden.