Byzantine–Mongol Alliance

[2][a][b] Byzantium attempted to maintain friendly relations with both the Golden Horde and the Ilkhanate realms,[5] and was caught in the middle of growing conflict between the two.

In the spring of 1242, John III Doukas Vatatzes, Emperor of Nicaea initiated a campaign against the Thessalonian Empire, and besieged its capital, Thessalonica.

[9] William of Rubruck also noted that he met an envoy of John III Doukas Vatatzes, Emperor of Nicaea, at the court of Möngke Khan around 1253.

Through Laskaris' shrewd deception, the embassy was convinced that Nicaea was a large and powerful state with a formidable army and covered entirely by mountains, thus making it exceedingly difficult for the Mongols to subjugate.

We will transmit to them your advice, so as to enlighten their deliberations, and will inform your Magnificence, through a secure message, of what will have been decided.Mamluk envoys were traveling through Constantinople to the Golden Horde in the summer of 1263.

[17][18] After 1295, Andronikos II offered Ghazan a marital alliance, in exchange for Mongol help to fight against the Turcomans at the Oriental frontier of the Byzantine Empire.

[17] Mongol control of western and central Anatolia was unstable, which allowed Turkmen groups to raid and cause damage to many frontier villages in the Byzantine Empire.