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I've hit a brick wall! I'm just wondering if any of you knowledgeable people could offer any gems of hope as I am no expert at this.
My 3rd Great Grandfather Henry Dugen 1853(abt)- 1875 lived in Barton upon Irwell / Irlam
•   He went by the name 'DugAn' on his death certificate 15th April 1875 (wife’s name and location confirm this is him)
•   He went by the name DugGAn on his burial record 18th April 1875 (age, date and location – same church as his marriage - make this highly likely to be the same person)
•   He went by the name DugEn on the marriage index & Certificate, 13th July 1873 (to Eliza Hurst) when he was 20 years old, living in Irlam. There is no Fathers name listed on the certificate, therefore I cannot trace him back any further. No signature either which I have assumed implies he is illiterate, and would explain all the different spellings of the surname.
•   He (his wife and his son) all went by the name DOugGIn on their son’s birth certificate (Thomas Henry Dugen/Douggin) Wifes name, location, date confirm this is highly likely to be him.
•   I can’t find him on any Census records
•   I can’t find his birth, but I have surmised that his birthday is between 16th April 1853 and 12th July 1853. This is worked out due to him being 20yrs old at his marriage on July 13th 1873, and being 21yrs old at his death on 15th April 1875.

What I’ve tried so far:
•   Ancestry search for D*g*n, its brought up a number of different spellings and outside possibilities, but none that I can actually verify.
•   No obvious link to the family when researching the witnesses of his marriage (they are all similarly aged)

So with no fathers name, or mothers name, and so many variations of surname, do I stand any chance of finding out any more than this? There is a strong family opinion that the family line originated in Ireland, perhaps that’s where he is from, but I can’t find anything that verifies it’s the same person (actually I cant find anything at all!).
Help?