The Britton surname

I didn't know it was French! From SurnameDB.com:

This interesting name does not mean anything to do with 'Britain' as in the British Isles of modern idiom, rather it is a national or ethnic name for someone from Brittany, France, a 'Breton'. In the 6th Century the Celtic speaking Bretons were driven to South West England (indeed the name Britton is frequently found around Bristol) by Anglo-Saxon invaders, and many Bretons came to England with William the Conqueror in 1066. The name can be spelt in several different ways in the modern idiom, ranging from, Britain, Britten, Brittan, Brittin and Brittain to Briton and Britney. The surname has long been established in Staffordshire; William Bryttayne married Elizabeth Cook in Betley, on November 28th 1559, and John Brittain was christened in 1589, also in Betley. In London, the christening of Edward Brittain was recorded on November 17th 1630 at St. Mary Whitechapel, Stepney. The first recorded spelling of the family name is shown to be that of John de Bretagne (witness), which was dated 1291 in the Assize Rolls, Staffordshire, during the reign of King Edward 1, known as 'The Hammer of the Scots', 1272-1307. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.