The imprint of the Tongan immigration is to be seen, not only in the blood of the tribes with whom the immigrants mingled, but in their mythology, for whereas the religion of the inland tribes is pure ancestor-worship, that of the coast tribes is overlaid with a mythology that is evidently derived from Polynesian sources. [Illustration: DESCENDANTS OF TONGAN IMMIGRANTS PERFORMING THE TONGAN DANCE _LAKALAKA_.] Early in the eighteenth century there seems to have been an upheaval among the inland tribes of Vitilevu which sent forth a stream of emigrants to the coast, whether as fugitives, or as voluntary exiles in search of new lands, there is no tradition to show. This event was destined to have a tremendous influence upon the political destiny of the islands, for among the emigrants was the tribe of Mbau, sturdy mountain warriors, still bearing in their physiognomy and dark complexion the proof of their Melanesian blood and their late arrival in the sphere of Polynesian influence. This tribe, humble as it was in its origin, was destined, partly through chance, partly by its genius for intrigue, to win its way within a century to the foremost position in the group. [Pageheader: THE RISE OF MBAU] Rewa, descended from the earliest settlers on the delta of the great river, could alone boast an ancient aristocracy and a complex social organization which entitled it to be called a confederation. The rest of the group was split up into tribes, little larger than joint families, which treated all strangers as enemies, and held their lands at the point of the spear. The Mbau people settled upon the coast about a mile from the islet now called by their name, but then known as Mbutoni, which is connected with the mainland by a coral reef fordable at high water. Upon the islet lived two tribes of fishermen, named Levuka and Mbutoni, who were supplied with vegetable food by the inland chiefs in return for fish. Being subject to the Mbauans, they supplied them with a navy, for a tribe lately descended from the mountains was distrustful of the sea. Wedged in between Verata on the north and Rewa on the south, Mbau was continually at war with one or the other. Her pressing need was men, "the men of Verata and Rewa" (to quote from the _meke_ that records her history), and as she held her own, those who had grievances against her powerful neighbours, broken tribes fleeing from their conquerors in the hills, flocked to her for protection, and her needs were satisfied. But her territory did not exceed ten square miles.