Later, the Seljuks invaded Mesopotamia with the support of Kurdish chieftains and tribes. Distinguishing between graves of chieftains, regents, kings, and status-seeking arrivistes is difficult. In the 18th century, several Gurjar chieftains and small kings were in power. Aboriginal Australians revered the hands of their deceased chieftains. The following year the local Viking chieftains of the Hebrides rebelled. Brute society is tribal and governed by chieftains. There were many instances of tribal raids and head-hunting led by the village chieftains. His successor Muhammad Shah II subdued most of the Rajput chieftains. Mornington consequently engaged the various Maratha chieftains in negotiations. Following the breakup of the Chera Kingdom, the chieftains of the region proclaimed their independence. It assigned Sufis as the chieftains of villages. Diegylis was considered one of the most bloodthirsty chieftains by Diodorus Siculus. Caesar ordered the Gauls to surrender their weapons and deliver their chieftains. The governor managed to defeat and make the chieftains accept Mughal authority. Wars began occurring between chieftains over land disputes.