English colonists, under petty leaders whose names have been forgotten,
seem to have pushed their way forward through the broad lowlands towards
Derby, Nottingham, and Leicester. They bore the name of Middle English.
Westward, again, other settlers raised their capital at Lichfield. These
formed the advanced guard of the English against the Welsh, and hence
their country was generally known as the Mark, or March, a name which
was afterwards latinized into the familiar form of Mercia. The absence
of all tradition as to the colonisation of this important tract, the
heart of England, and afterwards one of the three dominant Anglo-Saxon
states, leads one to suppose that the process was probably very gradual,
and the change came about so slowly as to have left but little trace on
the popular memory. At any rate, it is certain that the central ridge
long formed the division between the two races; and that the Welsh at
this period still occupied the whole western watershed, except in the
lower portion of the Severn valley.

The Welland, the Nene, and the Great Ouse, flowing through the centre of
the Fen Country, then a vast morass, studded with low and marshy
islands, gave access to the districts about Peterborough, Stamford, and
Cambridge. Here, too, a body of unknown settlers, the Gyrwas, seem about
the same time to have planted their colonies. At a later date they
coalesced with the Mercians. However, the comparative scarcity of
villages bearing the English clan names throughout all these regions
suggests the probability that Mercia, Middle England, and the Fen
Country were not by any means so densely colonised as the coast
districts; and independent Welsh communities long held out among the
isolated dry tracts of the fens as robbers and outlaws.

In the south, the advance of the West Saxons had been checked in 520,
according to the legend, by the prowess of Arthur, king of the