At a moment when prospects for internal reform in Asia Minor must have seemed quite dim to Andronikos, fortune intervened and raised hopes for a purely military solution. Late in 1301 a group of some 10,000 (Gregoras) to 16,000 (Pachymeres) Alans, half of whom were warriors, suddenly appeared on the northern frontier. Having fled southward from the Mongols, they petitioned the emperor for permission to enter the Empire and become soldiers. Andronikos seized the opportunity and enrolled them as supplemental mercenaries for two campaigns he had been planning. The Alans, generally considered a Christian Turkic people, had last fought for Byzantium during the eleventh and twenfth centuries as mercanaries.
In the spring of 1302, supplied with money, provisions and horses, the Alans were divided into three groups: one was led by the megas hetaireiarches Mouzalon to fight the Turks aorund Nikomedeia; another, led by Andronikos II's son Michael IX, marched south toward Magnesia. Their wives and children remained in Thrace. The Alans assigned to Mouzalon began to desert as soon as they had crossed into Asia. Bands of them indiscriminately plundered Byzantine territory, and by July 1302, Mouzalon's army consisted of barely 2,000 men, of which perhaps something more than half were Alans. While Mouzalon was defending Nikomedeia, an army composed of some 5,000 light cavalry drawn from nomadic tribes appeared between Nikomedeia and Nicaea. It was commanded by Osman, the Turkish emir of Bithynia. There on the plain of Bapheus Mouzalon's army was defeated. This first major victory for the founder of the Ottoman state, followed as it was by the pillage of the northwest corner of Asia Minor, hastened the flight of the Byzantine population westward.
Meanwhile, in April 1302 Michael IX departed for Asia with an army of Alans and other troops. His forces remained intact until they reached Magnesia on the Hermos River. Without fighting a pitched battle, the native Byzantine divisions eventually deserted and the Alan mercenaries likewise requested permission to abandon the expedition. Michael persuaded the Alans to remain with him another three months and wrote to Constantinople for additional money. At the end of the three months, the Alans refused to stay any longer and returned to Gallipoli. In a fortress in a hostile terriotry with only a fragment of his army, Michael found himself in a very difficult position. Secretly he fled to Pergamon, but as soon as those in Magnesia heard this news, the remainder of his army and many of the city's inhabitants followed him in a desperate scramble for safety. As for the Alans, after a period of negotiation, they returned their borrowed horses and arms to Andronikos and apparently departed from the Empire.
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The Catalans were a violent lot. Bloody confrontations erupted within days between the Catalans and the Genoese of Galata who had helped transport them to the city, and so Andronikos urged them to crosse the Sea of Marmara and billet outside the city of Kyzikos. There they spent the winter of 1303-04 and were joined by the Alans still in Byzantine service who had survived the battle of Bapheus, something less than 1,800 men, whose fates now intertwined with the Catalans. From the start the Alans and the Catalans had little love for one other, and it galled the Alans to learn how little they were being paid in relation to the enormous salaries of the Catalans. An altercation in April 1304 in Kyzikos left 300 Alans dead, including the son of their leader, George. Five hundrede then deserted, so that by May 1304 only a thousand Alans remained with the Catalans, and by the summer of 1304, most of these were gone as well.
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The Company spent the winter of 1304-05 at Gallipoli, virtually occupying the peninsula, and in the spring of 1305 they refused to move until their back pay was supplied. New negotiations with the emperor eased tensions, but then events took a significant turn for the worse. For reasons not entirely clear, Roger de Flor decided to visit Michael IX's camp in Adrianople in April 1305. Relations between the Catalans and the imperial army had been strained from the beginning, and in late 1304 Michael had to promise his troops that the Catalans would not join their ranks. Indeed Michael's army now included the Alans who had abandoned the Catalans and who just now had been recalled from the Bulgarian frontier where they had been campaigning with "the Persians of old, whom they called Tourkopouloi," both under the command of the Bulgarian Vojisil and "their own commanders." The Alans were present in Adrianople at the moment Roger de Flor made his fateful visit there. In Michael's camp the Alan leader George avenged the death of his son by murdering Roger, and a riot broke out in which, according to some accounts, all of Roger's 300-man escort was similarly dispatched.
When this news reached Gallipoli the Catalans vowed revenge. They attacked and plundered everything within their reach. Finally, in July 1305 the Catalans inflicted a crushing defeat on Michael IX's vastly superior forces near the town of Apros in Thrace. According to the anonymous Western author of the Advice for an Overseas Passage, "the Catalans... di not have even 2,500 cavalry, of which there were not 200 of military blood, while Michael was with 14,000 [cavalry] and a multitude of infantry." The Alan light cavalry, forming the left flank along with the Tourkopouloi, both still under the commando of Vojisil, withdrew after the first encounter, contributing decisively to the defeat. The Tourkopouloi the deserted to the Catalans and their Turkish allies. Gregoras adds that "these were the one thousand Tourkopouloi who followed Sultan Izz al-Din when he fled to the Romans, [and] received holy baptism," and whose numbers were augmented by subsequent children. Since the Alans did not have the option of joining the Catalans, they merely pillaged the area around Apros. After this battle the situation in Thrace became hopeless. Evidently the Alans spent the rest of 1305 and early 1306 plundering from winter quarters somewhere in Thrace. About the summer of 1306, with Thrace devastated by the Catalans, the Alans began a migration into Bulgaria, apparently seeking employment with the ruler there. At the foot of the Haimos range the Catalan force caught up with them, and there the remainder of the Alan warriors who had entered Byzantium in 1301 were annihilated and their wives and children enslaved.
The Alan episode was a major disaster, but since it occurred amid the Catalan crisis, contemporaries as well as modern historians have naturally tended to assign it only secondary importance. Andronikos' error in dealing with the Alans is clear. Every time the Alans deserted the Byzantined forces - either those of Mouzalon, Michael IX, or the CAtalans - they returned to Thrace, to their wives and children. With hindsight it is apparent that Andronikos should have counseled to follow John Vatatzes' example with the Cumans and to expend the effort, time and money to transport all the Alans as a group to Asia. Perhaps they still would have proved to be inadequate soldiers, bit if their families were in Asia, they would have had much more difficulty and much less reason to return to Thrace.