Complex sentence: By 1261, he had become a "despot", the title having been awarded to him by either Nicaean Emperor John IV Laskaris or his own suzerain, the ruler of Bulgaria, possibly Constantine Tih.
Split into simpler sentences: By 1261, he had become a "despot". The title was awarded to him by either Nicaean Emperor John IV Laskaris or his own suzerain, the ruler of Bulgaria, possibly Constantine Tih.