Battle of Marj Dabiq
Being of Abkhazian origin, he was the former Mamluk governor of Aleppo who contributed to the Ottoman victory at the Battle of Marj Dabiq. After the Ottoman conquest of the Mamluks and the end of the Mamluk Sultanate, the grand vizier Yunus Pasha was made the governor of Egypt. However, after Ottoman sultan Selim I found out about Yunus Pasha's corruption in governing, consisting of bribery and extortion, Hayır Bey was entrusted with the governorship of Egypt.