History Origin of Roman troops by region

[Maciamo]

Someone took the time to calculate the breakdown in origins for Roman troops during the imperial period in various parts of the empire based on surviving records.

 

[Tomenable]

Very interesting that in Iberia most soldiers were locals, while in Britain only 3%.

It seems Rome did not trust the Britons?

 

[Riverman]

What's the definition of "Danubian" in the British context? Is it "Balkan & Danubian" (Central-Eastern to South Eastern Europe) or more specific?