For most of the modern era, the eastern salient lay outside the control of Javanese political powers, which were typically based in Central Java. Sultan Agung of Mataram's conquest of eastern Java in 1614–1625, while managing to conquer Surabaya, Malang, Pasuruan and Madura, did not establish control over the eastern salient. A renewed campaign in 1640 brought the region under Mataram's control until Agung's death in 1645. His successor, Amangkurat I, tried unsuccessfully to subdue the region in 1647. From this point neither Mataram nor any other central Javanese polity would have effective control over the region. It remained outside Mataram's influence between the seventeenth to nineteenth centuries, when that region was developing the features and characteristics known today as essentially Javanese.
