Recent research of the UK genetic stock has shown that prior to the 1950's era of mass immigration 75% of our islands genetic heritage could be traced back to the 2,000 to 4,000 hunter gatherers who crossed the land bridge before the sea levels rose 12,000 to 14,000 years ago.
I seem to remember that recently they had shown that even that stock had formed genetic "kingdoms" on clear geographical lines then throw in Celts, Romans, Vikings, Angles, Saxons and Normans you might find some interesting things. But most likely, assuming your white British from a family that has several generations in the same area, most of your heritage will be from those hardy northern European hunter gathers that tamed the land after the last ice age.
Modern DNA is telling us some very interesting things.