All estimates of the size of Frankish and Muslim armies are uncertain, existing accounts indicate that it is probable that the Franks of Outremer raised the largest armies in the Catholic world. As early as 1111, the four crusader states fielded 16,000 troops to launch a joint military campaign against Shaizar. Edessa and Tripoli raised armies numbering 1,000–3,000 troops, Antioch and Jerusalem deployed 4,000–6,000 soldiers. In comparison, William the Conqueror commanded 5,000–7,000 troops at Hastings and 12,000 crusaders fought against the Moors at Las Navas de Tolosa in Iberia. Among the Franks' early enemies, the Fatimids possessed 10,000–12,000 troops, the rulers of Aleppo had 7,000–8,000 soldiers, the Damascene commanded 2,000–5,000 troops. The Artuqids could hire as many as 30,000 Turks, but these nomadic warriors were unfit for lengthy sieges. After uniting Egypt, Syria, and much of Iraq, Saladin raised armies around 20,000 strong. In response, the Franks quickly increased their military force up to around 18,000 troops, but not without implementing austerity measures. In the 13th century, the control of Acre's lucrative commerce provided the resources to maintain sizeable armies. At La Forbie, 16,000 Frankish warriors perished in the battlefield, but this was the last occasion when a united Jerusalemite army fought a pitched battle. During the 1291 siege of Acre, about 15,000 Frankish troops defended the city against more than 40,000 Mamluk warriors.