When the Romans came to Britain, and began their conquest or occupation of Lincolnshire, A.D. 50, they found extensive portions in the south-east of the county covered by great meres stretching many miles in extent. In the south-western part of the county were extensive forests; in the north-western part of the county was the island, now called the Isle of Axholme; but during the Roman occupation, and for centuries afterwards, were vast sheets of fresh water, with here and there an island or islet standing out above the surrounding meres. On the eastern side of the county, along the sea-board, the Romans built extensive banks or sea walls. Prior to the Roman occupation of Lincolnshire, a race or different races of people lived in the land we now know as the county of Lincolnshire; and it is of this period that we write regarding the earliest known races of mankind in the county. The different races of mankind in the Prehistoric Ages or Periods have been tabulated as— 1. The Eolithic Man, or Dawn of the Stone Age. 2. The Paleolithic Man, or the Old Stone Age, subdivided by Professor Dawkins as (_a_) The River Drift Man and (_b_) Cave Man.[2] 3. The Neolithic Man, or New Stone Age. 4. The Pygmy Man. 5. The Bronze Age, subdivided as Early and Late Bronze Periods. 6. The Prehistoric Iron Age. 7. The Iron Age of the Roman Period. We will deal with each of these races separately as they concern Lincolnshire. THE EOLITHIC PERIOD Of this period no traces of the work of mankind have been found in the county of Lincolnshire. It is a period which some experts strongly affirm show traces of the work of man in other more southern parts of Britain; so far as our experience by definite research has extended, we are not satisfied with the evidence offered, and prefer to keep an open mind. THE PALEOLITHIC PERIOD, OR OLD STONE AGE Many thousands of specimens of man’s work in this period or age have been found in Southern England—that is, as we define it south of a line drawn from the Severn to the Wash—but none of these old rough stone weapons have been found _in situ_ in Lincolnshire. From the facts presented by geology and a careful study of the county, it would appear that, while Paleolithic Man existed in the south of England, north of an imaginary line from the Wash to the Severn no traces of mankind have been found relating to the Paleolithic Period. It is probable that the great glaciers covered what is now known as Lincolnshire and Northern Britain in that period, and formed an inaccessible barrier to the progress of mankind. THE RIVER DRIFT PERIOD AND THE PERIOD OF CAVE MAN