Why British instead of Brittish?

[Penyafort]

Is there any reason for British, Britain and Briton being written with one single t, instead of an expected double one?

Thanks in advance.

 

[Delvo]

Why would two be expected? Because the vowel is /ɪ/ instead of /i/ or /ai/?

 

[bearded]

Would you also expect Italy to be spelt Ittaly?

 

[Platytude]

Why would two be expected? Because the vowel is /ɪ/ instead of /i/ or /ai/?

I guess so: cf. Scottish, Finnish, as opposed to Danish, Polish, Irish, Spanish.

 

[Welsh_Sion]

The Old English name was Brittisc or Bryttisc, which in later spelling was Brittish**, misspelt British under the Latin influence of Britannia.

The older name in the 'British' (Brittonic) Languages for their speakers was Brython < Brittones. The Bretons call their language Brezonek, and Cornish was once called Brethonec. All these imply an original *Brittonika.

It is said that the -tt- spelling in Latin appeared around CE 49/50 - a full century after the oldest form in Latin with one -t- as Britann-

** British still rhymes with 'skittish' (two t's) rather than 'whitish' (one t).

[See Morris-Jones, 1913: 4ff]

 

[merquiades]

Britannia in Latin had only one t.
This must be the origin.
Cross posted with Sion