Ptolemaic Egypt began when Ptolemy I Soter declared himself Pharaoh of Egypt in 305 BC and ended with the death of queen Cleopatra of Egypt and the Roman conquest in 30 BC. The Ptolemaic Kingdom was a powerful Hellenistic state, extending from southern Syria in the east, to Cyrene to the west, and south to the frontier with Nubia. Alexandria became the capital city and a center of Greek culture and trade. To gain recognition by the native Egyptian populace, they named themselves as the successors to the Pharaohs. The later Ptolemies took on Egyptian traditions, had themselves portrayed on public monuments in Egyptian style and dress, and participated in Egyptian religious life. Hellenistic culture continued to thrive in Egypt well after the Muslim conquest. The Ptolemies faced rebellions of native Egyptians often caused by an unwanted regime and were involved in foreign and civil wars that led to the decline of the kingdom and its annexation by Rome.