________________ 440 Homage to Vaisali independence, and Tirhut was probably under the rule of petty potentates. Early in the ninth century Gopala, the founder of the Pala dynasty, became ruler of Bengal, and towards the close of his life (cir. 850 A. D.) he extended his power westward over Bihar. In the 11th century Tirhut was wrested from the Palas by the ambitious kings of Chedi--a tract corresponding to the present Central Provinces; and in 1019 A. D. it acknowledged the sovereignty of Gangeyadeva,* who aimed at attaining paramount power in Northern India. The end of that century witnessed the rise of the power of the Sena kings, who not only wrested their eastern provinces from the Palas, but also appear to bave carried their arms northwards to North Bihar. Mithila formed the north-western province of the kingdom of the Senas, and their rule in this part of Bibar is still commemorated by the use of the Lakshmana Sena era, the first current year (1119-20 A. D.) of which was apparently the date of either the accession or the coronation of Lakshmana Sena, the last great king of the Sena dynasty. Muhammadan Period In the beginning of the 13th century the tide of Mubammadan conquest swept over Bihar, but it does not appear to have reached far north of the Ganges; for it is not till the time of Ghias-ud-din Iwas, the Muhammadan Governor of Bengal between 1211 and 1226, that we learn that he carried the banner of Islam into the territories of the Raja of Tirhut, which had never before been subdued, and compelled him to pay tribute. This appears, however, to have been rather a successful invasion than an effectual conquest of the country; for a local dynasty of Hindu kings was established about this time at Simraon in the north-east corner of the Champaran district, and these kings succeeded in maintaining their rule over Tirbut for over a century, until the invasion of Tughlak Shah in 1323 finally put an end to their independence. Simraon Dynasty Of the earlier kings of this dynasty, we have only traditional accounts. Its founder was one Napa or Nanyupa Deva, (18] who is said to have established himself at Simraon, and to have eventually subdued the whole of Mithila and to have overcome the king of Nepal. Tradition relates that one of his sons reigned in Nepal, and the other, Ganga Deva, in Mithila. Here he is credited with having introduced the system of fiscal divisions of parganas for the purposes of revenue administration; while a chaudhri or headman was appointed in cach pargana to collect * Bendall's History of Nepal, J. A. S. B., Part I, 1903.
