Persian held Egypt, Egypt was conquered by the Persian ruler Cyrus and his son Cambyses II. Cyrus the Great took over for his father before him and led the Persian armies against the Medes, Lydia and Babylon. Cyrus then died passing the torch to his son Cambyses II who ruled for 7 years continuing his father's work on the conquest of Egypt. After Cambyses death a power struggle took hold, Darius the Great ended up taking over, Darius had a tenuous relation the the royal chain but was declared king anyway. Darius’s first conquering was at Susa and continued conquering after that. Under Cyrus the Great, Cambyses II and Darius the Great, the Persian Empire eventually became the largest empire in human history up until that point, ruling and administering over most of the then known