Osman was born ca. 1663 in the Morea (Peloponnese) peninsula in to Albanian parents, but his family also lived in Konya in Anatolia where his father worked for the Ottoman administration. At a young age he entered the Sultan's service, enrolling in the corps of the "kozbekçi" and then the "pandurs". By the age of 24, he had already risen to the rank of "beylerbey". Sent on a mission to the Governor of Egypt, his ship was attacked "en route" by a Spanish privateer. Osman was captured after a fight, in the course of which he received a wound which left him lame in one foot for life, earning him the epithet ""Topal"" (Turkish for "lame").