The cycle of the mythological stories which group themselves round the early invasions of Erin is sparsely represented in Irish manuscripts. Not only is their number less, but their substance is more confused than that of the other cycles. To the comparative mythologist and the folk-lorist, however, they are perhaps the most interesting of all, as throwing more light than any of the others upon the early religious ideas of the race. Most of the sagas connected with this pre-Milesian cycle are now to be found only in brief digests preserved in the Leabhar Gabhála,[1] or Book of Invasions of Ireland, of which large fragments exist in the Books of Leinster and Ballymote, and which Michael O'Clery (collecting from all the ancient sources which he could find in his day) rewrote about the year 1630. This tells us all the early history of Ireland and of the races that inhabited it before our forefathers landed. It tells us of how first a man called Partholan made a settlement in Ireland, but how in time he and his people all died of the plague, leaving the land deserted; and how after that the Nemedians, or children of Nemed, colonised the island and multiplied in it, until they began to be oppressed by the Fomorians, who are usually described as African sea-robbers, but the etymology of whose name seems to point to a mythological origin "men from under sea."[2] A number of battles took place between the rival hosts, and the Fomorians were defeated in three battles, but after the death of Nemed, who, like Partholan, died of a plague, the Fomorians oppressed his people again, and, led by a chief called Conaing, built a great tower upon Tory, _i.e._, Tower Island, off the north-west coast of Donegal. On the eve of every Samhain [Sou-an, or All Hallow's] the wretched Nemedians had to deliver up to these masters two-thirds of their children, corn, and cattle. Driven to desperation by these exactions they rose in arms, stormed the tower, and slew Conaing, all which the Book of Invasions describes at length. The Fomorians being reinforced, the Nemedians fought them a second time in the same place, but in this battle most of them were killed or drowned, the tide having come in and washed over them and their foes alike. The crew of one ship, however, escaped, and these, after a further sojourn of seven years in Ireland, led out of it the surviving remnants of their race with the exception of a very few who remained behind subject to the Fomorians. Those who left Ireland divided into three bands: one sought refuge in Greece, where they again fell into slavery; the second went--some say--to the north of Europe; and the third, headed by a chief called Briton Mael--Hence, say the Irish, the name of Great Britain--found refuge in Scotland, where their descendants remained until the Cruithni, or Picts, overcame them.