In the face of these catastrophes, Cassander sued for peace, but Antigonus rejected the claims, and Demetrius invaded Thessaly, where he and Cassander battled in inconclusive engagements. But now Cassander called in aid from his allies, and Anatolia was invaded by Lysimachus, forcing Demetrius to leave Thessaly and send his armies to Asia Minor to assist his father. With assistance from Cassander, Lysimachus overran much of western Anatolia, but was soon (301 BC) isolated by Antigonus and Demetrius near Ipsus. Here came the decisive intervention from Seleucus, who arrived in time to save Lysimachus from disaster and utterly crush Antigonus at the Battle of Ipsus. Antigonus was killed in the fight, and Demetrius fled back to Greece to attempt to preserve the remnants of his rule there. Lysimachus and Seleucus divided up Antigonus's Asian territories between them, with Lysimachus receiving western Asia Minor and Seleucus the rest, except Cilicia and Lycia, which went to Cassander's brother Pleistarchus.