Question: What is the date of death of Michael Asen Iv Of Bulgaria's father?
Sentence (from "Kaliman Asen II of Bulgaria"): Asen II's mother is unknown, and attempts to identify her as a Serbian princess are based on the erroneous identification of Kaliman Asen II with the" sebastokrator" Kaloyan, who was still alive in 1258/ 59.
Relevant evidence: No