How did Cambyses II establish Persian rule in Egypt?

Cambyses II established Persian rule in Egypt in 525 BCE through a combination of strategic alliances and military force. To facilitate the invasion, he secured assistance from Polycrates of Samos, utilized critical intelligence from the Greek general Phanes, and obtained support from Arab tribes to provide water for crossing the Sinai Peninsula.1

The decisive military engagement occurred at the Battle of Pelusium, where Cambyses defeated the Egyptian pharaoh Psamtik III. Following this victory, Cambyses captured the cities of Heliopolis and Memphis, effectively causing Egyptian resistance to collapse. Upon consolidating his control, Cambyses had himself crowned as pharaoh, marking the beginning of the 27th dynasty. While later Greek accounts by Herodotus characterized him as a tyrant, contemporary Egyptian evidence suggests he initially adopted a more conciliatory policy toward local customs and traditions.123