Aristotle was born in Macedonia in 384 bc. For twenty years he studied at Athens in the academy of Plato, before becoming tutor of the young Alexander the Great. When Alexander became king of Macedonia in 336, Aristotle returned to Athens and founded his own school and research institute, the Lyceum. Aristotle fled to Calcis in 323 in the aftermath of Alexander's death, where he died a year later. P J Rhodes is Professor of Ancient History at Durham University, and is a Fellow of the British Academy. His major work is Commentary on the Aristotelian Athenation Politeia.