For a few centuries, Christian leaders said they were concerned about protecting the Holy Land (Jerusalem and the surrounding area) from so-called infidels (they meant Muslims, and possibly Jews, but less so). From 1095 until 1291 there was a steady presence of Christian pilgrims and fighters in the Holy Land. Travel during this period was extremely dangerous and violent, and eventually groups of armed knights arose to escort travelers to and from the area. Oh yeah, they’d fight off anyone who tried to attack Christians in general, leading to many bloody and ruthless battles. The first of those armed orders, formally called the Sovereign Military and Hospitaller Order of St. John of Jerusalem, of Rhodes, and of Malta, or more commonly known as the Knights Hospitaller, was founded on this date,15 February 1113.
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By the time the First Crusade was called in 1095, Muslims had controlled most of the territory in the Middle East for hundreds of years – they’d even had a Golden Age of art, science, mathematics, and more during that time. So Muslim control of Jerusalem wasn’t anything new. What was new was the decline of the Byzantine Empire – an Eastern Orthodox branch of Christianity – and its collusion with the Western Catholic Church to remain in power. At the urging of the Byzantine Emperor, who had an on-again, off-again series of battles with various Muslim leaders over territory, the Pope called for a Crusade in 1095 to regain Jerusalem.
There was a larger and more enthusiastic answer to the call than the Pope or Byzantine Emperor expected. Many went for pilgrimage to a holy site or because the Pope guaranteed religious salvation if a person died while on Crusade. Others were satisfying feudal or political obligations, while others, in true capitalist manner, saw economic opportunities for plunder or renown. So many people joined the Crusade from all across Europe that by 1099 there were enough knights and other soldiers to capture small territories, including Jerusalem, and set up a Crusader state. These Crusader States (or Kingdoms) became battlegrounds for more Crusaders for the next 200 years.
Into this disputed land, the Knights Hospitallers formed. They were founded in a medieval hospital in Jerusalem meant to care for sick and poor pilgrims. They soon expanded to include hostels and lodging for travelers along the route through Europe into the Holy Land. The Pope formally recognized them with a papal bull on this date in 1113, with their headquarters in that original Jerusalem hospital. They steadily acquired wealth and lands for the next few centuries.
Muslim forces recaptured Jerusalem in 1187, so the Hospitallers moved their headquarters first to Margat (Syria) and then, in 1197, to Acre (now known as Akko or Akka in Northern Israel). When the Crusader States ended after the fall of Acre in 1291, the Hospitallers moved to Limassol in Cyprus. In 1309 they acquired the island of Rhodes (sadly, not the Colossus too, as that had been destroyed centuries before), which they came to rule as an independent state. It was at this point that the Hospitallers basically stopped traveling to or fighting in the Holy Land.
Instead, the power and prestige of the knights had suffered. Though they basically ruled Rhodes as an independent kingdom for another 200 years, they had little presence in their old bases throughout Europe. When the Ottoman Sultan Suleiman the Magnificent laid siege to Rhodes and conquered it in 1523, the Hospitallers roamed until relocating their headquarters on Malta in 1530. Suleiman wasn’t content to let the still dangerous Hospitaller forces control an island so close to his territory, so sent an army to invade in 1565 (known to history as the Great Siege of Malta). Through luck and brilliant leadership from Grand Master Jean Parisot de Valette, the Hospitallers repelled Suleiman’s invading force, though most of the cities and villages of the town were destroyed. Undeterred, they rebuilt the island and founded a new capital on Malta, Valletta, named after their Grand Master.
Still, by now hey were reduced to a small force on their one island on Malta and had little income other than what they could obtain from battling Barbary pirates in the Mediterranean or by working as mercenary soldiers, sailors, and pirates. Definitely no Holy Land protection racket. The Hospitallers managed to struggle through as a largely symbolic and relatively independent weak state until Napoleon captured Malta in 1798 during his campaign to Egypt (where he later famously, and possibly apocryphally, blew off the nose of the Sphinx). The Hospitallers fled the island and were offered refuge by various European rulers. When Malta was given to the British after the Napoleonic wars, they again had no permanent home until they became established in Rome in 1834, where they remain today (almost like latter-day Popes themselves).
From 2000 to 2013, the Israel Antiquities Authority rediscovered and excavated the original Hospitaller home in the Christian Quarter of the Old City of Jerusalem, the Hospital of Saint John, which had been built between 1099 and 1291. The 150,000 square feet building could have accommodated up to 2,000 patients, from all religious groups, and also served as an orphanage where the children often became Hospitallers after growing into adulthood. That’s as good a way as any to gather new recruits.