Albion
This is a historic name for the island of Great Britain. It might come from the Latin word for “white,” referring to the white cliffs of Dover.
Why I Looked It Up
One of the antagonists in Slow Horses was a domestic terrorist group named the “Sons of Albion.”
Postscript
Added on
I found a 1985 book called “Albion’s Seed,” which details what happened to four distinct ethnic groups that migrated from the UK to the United States.