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. (May 2015)
The main turning point in the Crusades was in 1187 when, after the pivotal Battle of Hattin, the Christians lost Jerusalem to the forces of Saladin. In the same year, Saladin was able to conquer a great part of the Kingdom of Jerusalem including Acre and Jerusalem. This led to the Third Crusade, during which Acre was besieged and eventually fell in the hands of the Christians in 1191; it became the base of operations and capital of the Kingdom of Jerusalem for most of the next hundred years. The religious orders had their headquarters in or near Acre, from which they made crucial decisions in military and diplomatic efforts. For example, when the Mongol forces came in from the East in the mid-13th century, the Christians saw them as potential allies, but also maintained a position of cautious neutrality with the Muslim forces of the Mamluks. In 1260, the Barons of Acre allowed the Mamluks to pass through their territory unhindered, which enabled the Mamluks to achieve a decisive victory against the Mongols at the pivotal Battle of Ain Jalut in Galilee.
However, most relations with the Mamluks were not as cordial. With the rise of the Mamluk Sultanate in Egypt in 1250, an even more dangerous and formidable enemy than the Ayyubids with heavy cavalry to match Crusader knights, the destruction of the remaining Crusader territories gathered pace. They also proved to be much more hostile. After the Battle of Ain Jalut, Mamluk forces began attacking Crusader holdings as early as 1261 under Sultan Baibars. In 1265, Caesarea, Haifa, and Arsuf all fell to the Sultan. The following year saw the loss of all the important Latin holdings in Galilee. In 1268 Antioch was taken.
To help redress these losses, a number of minor Crusading expeditions left Europe for the East. The abortive Crusade of Louis IX of France to Tunis in 1270 was one such attempt. The minor Ninth Crusade of Prince Edward (later King Edward I) of England in 1271–1272 was another. Neither of these expeditions was capable of giving any sound assistance to the beleaguered Latin states. The forces involved were too small, the duration of each of the Crusades too short, the interests of the participants too diverse to allow any solid accomplishment.
Pope Gregory X labored valiantly to excite some general enthusiasm for another great Crusade, but he labored in vain. The failure of his appeal was variously ascribed by the Pope's advisors to the laziness and vice of the European nobility and to clerical corruption. Though each of these factors may have been in part to blame, a more basic reason for the failure seems to have been the debasement of the ideal of the Crusade itself. The use by Gregory X's predecessors of the label and privileges of the Crusade to recruit armies which could fight the Papacy's European enemies had done much to throw the whole movement into disrepute.
In any event, no Crusade of any major importance was forthcoming, despite the Pope's best efforts. Meanwhile, the attacks on the Latin East continued, as did also the internal difficulties within what was left of the Latin Kingdom. By 1276, the situation, both external and internal, had become so perilous that the "King of Jerusalem" Henry II withdrew from Palestine altogether to take up his abode on the Island of Cyprus. The desperate plight of the Latin Kingdom worsened. In 1278, Lattakia fell. In 1289 Tripoli was lost in the Fall of Tripoli.
The Mamluks were led by Sultan Al-Ashraf Khalil, son of Qalawun. Qalawun had begun preparations for the siege but died in November 1290.
Decades of communications between the Europeans and the Mongols, towards the possibility of creating a Franco-Mongol alliance, had not produced any noticeable result, and attempts to raise a new army from Italy merely gave an excuse for the final attack by the Muslims.
Muslim attack on the city
Following the fall of Tripoli, king Henry of Cyprus sent the senechal Jean de Grailly to Europe to warn European monarchs about the critical situation in the Levant. Jean met with Pope Nicholas IV who shared his worries and wrote a letter to European potentates to do something about the Holy Land. Most however were too preoccupied by the Sicilian question to organize a Crusade, as was king Edward I too entangled in troubles at home.
One Arabian account claims that an affair between a rich young wife of the city and a Mussulman was discovered by the husband who:
gathers together some friends goes out from Ptolemais [...] and immmolates them both to his injured honour. Some Mussulmans are drawn to the spot, the Christians come up in still greater numbers, the quarrel becomes angry and general and every Mussulman is massacred.
— The History of the Crusades, Vol. 3, p.73, Michaud and Robson
The Christians feared this would give the Sultan a pretext on which to renew the war and petitioned the pontiff to send further aid. The aid according to Michaud came in the form of 25 Venetian galleys carrying 1600 men "levied in haste in Italy". Other sources claim 20 galleys of men to be peasants and unemployed townfolks from Tuscany and Lombardy led by
Nicholas Tiepolo, the son of the Doge, who was assisted by the returning Jean de Grailly and
Roux of Sully. These were then joined by five galleys from king James II of Aragon who wished to help despite his conflict with the Pope and Venice.
These reinforcements from Italy were ill-disciplined and having no regular pay resorted to pillaging indiscriminately from both Muslims and Christians before setting out from Acre. According to Runciman they attacked and killed some Muslim merchants around Acre in August 1290, though Michaud's account reports that they instead laid waste towns and villages all about with pillaging and massacre. In any case, if the Sultan Qalawun were in need of a further pretext for attack, he certainly now had one—Qalawun asked for the men guilty of the killing to be remitted to him so that he could apply justice. After discussions of the apparent remitting the Christian criminals from Acre's jails, an idea of Guillaume de Beaujeu, the Council of Acre finally refused to remit anybody to Qalawun, and instead tried to argue that the killed Muslims had died because of their own fault.
Although a ten-year truce had been signed in 1289, Qalawun deemed the truce void following the killings. By October, Qalawun had ordered a general mobilization. Though the Sultan died in November, he was succeeded by his son Khalil (some accounts Chalil), who would lead the forces attacking Acre.