Stranded deep in enemy territory the Spartan general Clearchus and the other Greek senior officers were subsequently killed or captured by treachery on the part of the Persian satrap Tissaphernes. Xenophon one of three remaining leaders elected by the soldiers played an instrumental role in encouraging the Greek army of 10000 to march north across foodless deserts and snow-filled mountain passes towards the Black Sea and the comparative security of its Greek shoreline cities.