The root of the name Britannia

The name Britannia (Old French Bretaigne) is a Latinisation of the native Brittonic word for Great Britain, Pretanī, which also produced the Greek form Prettanike or Brettaniai. In the 2nd century, Roman Britannia came to be personified as a goddess, armed with a spear and shield and wearing a Corinthian helmet.

The root of the name Britannia occurs in Irish in the form of Birgita in recent times: Britannia can be identical to Birgitannia: "the land of strength or high godess" in Irish.