Treaty of Chernomen

[2] Michael Shishman, who fought against Andronikos III three years earlier, was interested to help because he was in strained relations with Serbia after his divorce with Anna Neda and was disturbed by the marriage of Stephen Dečanski to the cousin of the old emperor Maria Palaiologina.

Since the negotiations were supposed to be secret, they used for pretext the desire of the Byzantine empress Rita of Armenia to meet her daughter Maria Palaiologina, whom she had not seen for 23 years and Andronikos III was allegedly anxious to see his sister as well.

[5] The treaty was signed without major obstacles as both sides had clear interest of the alliance — Michael Shishman wanted a reconquest of Macedonia, while Andronikos III was preparing for the final confrontation with his grandfather.

[6] Backed on the treaty, when hostilities were resumed in the autumn of 1327, Andronikos III was able to quickly submit Macedonia and in January 1328 captured Salonika, the second most important city in the Byzantine Empire.

[11][12] As the relations between Bulgaria and Serbia were deteriorating and the two countries were on the course of war,[8] Michael Shishman and Andronikos III organised a final meeting at Krimni between Sozopol and Anchialos in the beginning of 1329 and agreed to a "lasting peace and eternal alliance".