well, I've had a few day's to mull things over and i will summarise them here to see what you think.
There seems to be three Herbert Ravens in the frame .
1, The Herbert Raven in the 1911 census is in prison , it states that he is married , a labourer, 26 years old born in Nottingham . I can find no details of a birth in1885 for this so its not clear on his age. In the 1911 census Sarah Ann Raven is not living with her Husband for what ever reason, could it be her Husband is in prison?
2, In the 1901 census there is a Herbert Raven in prison in York , it states that he is a soldier , he was born 1880 in St Saviours Nottingham does any one know this place? it says that he is married but looking on Ancestry i could find no marriage details leading up to 1901.
He appears in no other census and i cannot find him in the births .
He joined the forces in 1900 Dec 5 and his age is 20 years and 9 months , i would guess that he was born in MARCH .
His next of kin is his mother ( not his wife ) Emma Thomas who I'm quite sure was Emma Raven 1855.
Emma Thomas lives at 11 MARKET SQUARE
3, Herbert Barnes Raven , born in 1878 MARCH on birth records. he appears on no census that i can see.
The Herbert Raven service record says he married Sarah Ann Burton in 1905 and his age is 39 years and 8 months on the 19 Oct 1915 that would make it about 1876 Feb /MARCH but on there marrage certificate he puts his age at 23 so this Herbert Raven is fiddling his age when suits him.
Also Herbert Barnes Raven in 1915 put his mother as next of kin as A Raven living in MARKET SQUARE . I looked on Ancestry and could find no marriage details of A Raven.
Also in the Nottinghamshire Guardian Jan 8 1898 he was in trouble with the police, his age is 21 .
With all the information that i have,i have a hunch that may be the Herbert Raven in my family tree is in fact all the above or it could be that all the three Herbert Ravens here are a dodgy bunch .
I have sent off for the Birth certificate of Herbert Barnes Raven , i hope that this will show his parents on it and lead on to more information.
Luke