The Rise of the Ottoman Threat

In the early 15th century, the Mediterranean world stood at a crossroads. The once-mighty Byzantine Empire, now reduced to little more than Constantinople and its hinterlands, watched uneasily as the Ottoman Turks expanded their domains. Meanwhile, the Knights Hospitaller, having established their stronghold on Rhodes after their expulsion from the Holy Land, found themselves in an increasingly precarious position.

The ascension of Mehmed I in 1413 marked the end of the Ottoman Interregnum, a period of civil war that had temporarily weakened the empire. Known as “the Gentleman” for his diplomatic approach, Mehmed I pursued relatively conciliatory policies, even seeking the Hospitallers’ assistance against rival Anatolian beyliks. Yet the knights, ever cautious, navigated a delicate balance between Ottoman power, Venetian and Genoese interests, and the smaller Muslim principalities of Asia Minor.

The Hospitallers’ Pirate Diplomacy

To maintain their relevance—and placate a papacy increasingly frustrated by their lack of militant action—the knights adopted a policy of sanctioned piracy. Officially, individual knights were permitted to raid Muslim shipping under the guise of holy war, though in practice, their targets often included Christian vessels. This “gray policy” allowed the order to distance itself from the raids while still benefiting from the spoils.

One notorious figure, the Catalan pirate Nicholas Samper, operated under the Hospitallers’ banner, terrorizing both Muslim and Christian ships alike. When victims protested, the knights disavowed responsibility, claiming these were merely the actions of “private citizens.” Yet the order’s leadership tacitly approved, issuing licenses that even permitted attacks on vessels from nations with which Rhodes had peace treaties.

This strategy, however, sowed seeds of future conflict. In 1412, the Genoese lord of Lesbos, James Gattilusi, had enough. After yet another raid on Turkish merchants near his island, he captured the Hospitaller crew and threw them in prison—a stark warning that Rhodes’ maritime predation would not go unchallenged forever.

The Gathering Storm

By the 1420s, the geopolitical landscape shifted dramatically. Murad II, succeeding his father Mehmed I, abandoned conciliation for expansion. The Hospitallers, long accustomed to playing regional powers against one another, now faced a resurgent Ottoman threat on one flank and Mamluk hostility on the other.

The 1444 Mamluk invasion of Cyprus proved a devastating blow. Egyptian forces sacked the Hospitaller stronghold of Kolossi Castle, forcing the knights to contribute heavily to King Janus’ ransom. Financially crippled, the order watched helplessly as Ottoman conquests in Anatolia brought Muslim armies to the very shores facing Rhodes.

The Great Siege of 1480

When Mehmed II—the conqueror of Constantinople—turned his gaze toward Rhodes in 1480, the knights stood at their moment of reckoning. Under Grand Master Pierre d’Aubusson, they had spent decades fortifying the island, constructing concentric walls, bastions, and a massive chain across the harbor entrance.

The Ottoman assault, led by Mesih Pasha (a Byzantine-descended general), focused initially on the seaward defenses. For weeks, Turkish artillery pounded the Tower of St. Nicholas, while sappers tunneled beneath its foundations. Yet the knights, fighting with the desperation of men who knew surrender meant impalement, repelled wave after wave.

The turning point came on July 28, when Mesih Pasha launched his grand assault on the Jewish Quarter’s walls. As Ottoman troops poured through breaches, the 57-year-old d’Aubusson—already wounded three times—led the countercharge in person. A Turkish spear pierced his lung, yet he continued fighting until collapsing. His heroism rallied the defenders, who ultimately drove the invaders back with horrific losses.

After 89 days, with his army decimated by combat and disease, Mesih Pasha withdrew. Rhodes had survived—but the respite would prove temporary.

The Fall of Rhodes (1522)

Mehmed II’s death in 1481 granted the knights a generation’s reprieve, but his grandson Suleiman the Magnificent proved even more formidable. In 1522, the sultan arrived with an army dwarfing the 1480 invasion force. Against 100,000 Ottomans, Grand Master Philippe Villiers de L’Isle Adam could muster barely 7,000 defenders.

The siege followed a grimly familiar pattern: relentless bombardment, tunneling, and bloody assaults. Innovations like Venetian engineer Gabriele Tadini’s acoustic early-warning system gave the defenders an edge, but attrition took its toll. By December, with the Spanish breach overrun and supplies exhausted, L’Isle Adam negotiated honorable terms.

On January 1, 1523, the surviving knights sailed from Rhodes, ending their 213-year reign. Yet their story wasn’t over—within a decade, they would establish a new bastion on Malta, where another epic siege awaited.

Legacy of the Rhodian Era

The knights’ two-century tenure on Rhodes represented both the twilight of crusading idealism and the dawn of early modern statecraft. Their hybrid identity—part monastic order, part naval power—allowed them to outlast every other crusader state.

Strategically, their defiance disrupted Ottoman expansion, buying critical time for Christendom. Culturally, Rhodes became a rare enclave where Greek scholars, Italian artists, and French knights coexisted—a microcosm of Mediterranean exchange.

Most enduringly, the sieges of Rhodes entered European consciousness as symbols of Christian resistance. Guillaume Caoursin’s bestselling account of the 1480 siege and the dramatic last stand in 1522 inspired generations, proving that even in retreat, the Hospitallers could claim a kind of victory—the victory of legend.