Hu Gadarn, the Joshua of the Old Testament, came to Britain in the early to mid 1300's B.C.
A fragmentary Welsh record, called the Welsh Triad, reads as follows:
'First was the race of the Cymry, who came with Hu Gadarn to Yns Prydain.' Hu came from the 'land of summer'Read more here...
-- a land located somewhere in what later constituted the realm of Constantinople (capital of the eastern Roman Empire)