 In 1363 he marched against his first brother Shah Mahmud, who had been given control of Isfahan, although a peace was soon brokered.In the following year however, Shah Mahmud, with the support of his father-in-law Shaikh Awais Jalayir of the Jalayirids, invaded Fars and captured Shiraz.Shah Shoja would not be able to reconquer his capital until 1366.