However, having determined to attempt at once his reforms in the state, Cleomenes bribed the ephors to send him on an expedition. He also won the favour of large numbers of the citizens with the help of his mother Cratesicleia, who assisted him liberally in providing ways and means, and shared his ambitions. It is even said that although she had no desire to marry again, for the sake of her son she took a husband who was foremost among the citizens in reputation and influence.
So Cleomenes led forth his forces and occupied Leuctra, a stronghold of Megalopolis. The Achaeans, under the command of Aratus, came swiftly to the aid of their allies against him, and Cleomenes, after drawing up his forces under the very walls of the city, was worsted at one point. But Aratus would not permit the Achaeans to cross a certain deep ravine, and brought his pursuit to a stop.
Lydiadas the Megalopolitan, however, chafing at this, dashed on with the horsemen under his command, and pursuing the enemy into a place full of vines, ditches, and walls, had his ranks broken and thrown into disorder thereby, and began to fall into difficulties. Cleomenes, observing this, sent against him his Tarentines and Cretans, at whose hands Lydiadas, defending himself sturdily, fell. At this the Lacedaemonians took courage and with a shout fell upon the Achaeans and routed their entire army.
Great numbers of them were slain, and their bodies Cleomenes restored at the enemy's request; but the body of Lydiadas he asked to have brought to him, arrayed it in a purple robe and put a crown upon the head, and then sent it back to the gates of Megalopolis. This was the Lydiadas who renounced the tyranny, gave back to the citizens their freedom, and attached the city to the Achaean league.