When and how was the Persian kingdom established?

The ancient Persian state was created in the middle of the 6th century BC. Its founder was Cyrus 2, who was able to seize power in the Median kingdom and turn it into an empire. This is how the power of the Achaemenid dynasty was established, which ruled the Persian state for over 200 hundred years. The decline of Persia refers to the period of the reign of Darius III, who could not stop the advance of Alexander the Great and lost his power.