Seleucus I Nicator, of the Seleucid Empire, fought a Seleucid–Mauryan War with Chandragupta Maurya to retake the Indian satrapies of the Macedonian Empire. The war ended with the annexation of the Indus Valley region and a portion of Afghanistan to the Mauryan Empire, with Chandragupta gaining control of the areas he wanted and the two forces forming a marriage alliance. Following the battle, the Mauryan Empire established itself as the dominant power in the Indian Subcontinent, while the Seleucid Empire concentrated on defeating its rivals in the west.