The north coast was, however, Muslim as far as Surabaya and were often at war with the interior. Of these coastal Muslim lords, some were Javanese who had adopted Islam, and others were not originally Javanese but Muslim traders settling along established trading routes including Chinese, Indians, Arabs and Malays. According to Piers, these settlers and their descendants so admired Javanese Hindu-Buddhist culture that they emulate its style and were thus themselves becoming Javanese.