The Achaemenid Empire (c. 550-330 BCE) was the first great Persian political entity in Western and Central Asia which stretched, at its peak, from Asia Minor to the Indus Valley and Mesopotamia through Egypt. It was founded by Cyrus II (the Great, r. c. 550-530 BCE) whose vision of a vast, all-inclusive Persian Empire was, more or less, maintained by his successors.
This is a companion discussion topic for the original content at https://www.worldhistory.org/article/1518/achaemenid-kings-list--commentary/.