Battle of Ipsus
Seleucus further made claim to the former satraps in Gandhara and in eastern India. However these ambitions were contested by Chandragupta Maurya, resulting in the Seleucid–Mauryan War (305–303 BC). The conflict was ultimately resolved by a treaty resulting in the Maurya Empire annexing the eastern satraps. Additionally, a marriage alliance between the two empires was formalized with Chandragupta marrying Seleucus' daughter. Furthermore, the Seleucid Empire received a considerable military force of 500 war elephants with mahouts, which would play a decisive role against Antigonus at the Battle of Ipsus in 301 BC. In 281 BC, he also defeated Lysimachus at the Battle of Corupedium, adding Asia Minor to his empire.