A 1917 newspaper article stated the following: Jonah was born in Russia in 1894
He came to England at age 4, some years after his father David settled in Blackburn
He became a British subject when his father naturalized but was born in Russia.
So there were complications as to his conscription obligation
At the time Jonah was a dental operator at Petworth St., Cheetham, Manchester
He has/had a relationship with Rachel Davis.
Child(ren):
In the British WW1 archives, there is a medal card for Private Jonah Blain of the Royal Army Medical Corps who enlisted 1 October 1916 and was discharged on 20 February 1919.
Presumably, he was a dentist in the RAMC.
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