Hi Louise,
What I tried to do was work on what I had and try to find the most likely next step on the RootsIreland.ie website. Some might be leaps and some may be true. The next step would be to spend some money on actual documents.
As you found on the UK census from 1851, Michael Gallacher is listed as born in 1816 in Sligo Ireland. The first bit of luck is a search of the Irish Baptismal/Birth records for a Michael Gallacher (searching all possible spellings of this common surname) born in 1816 brings up only 1!
I purchased the church Baptism record : he was born 17th Sept 1816 in Riverstown Co Sligo and baptised Roman Catholic. His parents were William and Honora Gallaher. I have found other records on other sites FamilySearch.org which also lists these same parents (although with Irish spelling of William, Guliellmi) - christened in Taunagh.
From this it is relatively easy to search for the rest of the family/children as you can put the parents names into the search detaisl. They had 6 children I think John (born 1814) Michael (born 1816) Maria (1820) Bridget (1823) James (1825) Thomas (1828).
William and Honora were married in 1814 in a churchmarriage in County Sligo.
I then searched for a marriage for a michael gallacher to an ellen (I did not know you had found an Ellen Ford on a birth certificate then) across a very wide range of dates (1832 to 1850) ie from the age of 16 to the age when he turned up in the UK. This turned up only one - Ellen McGlone born in 1824 (about right for the subsequent census details in the UK)
I paid for the church marriage record which shows this Michael married on the 30th of December 1849 in Killasser County Mayo only about 20 - 30 miles from where he grew up, to a girl called Ellen McGlone from County Armagh born in 1824 according to the rootsIreland records.
The marriage appears to have been quick or rushed (who gets married on the day before new years eve in the winter of a potato famine??) IF their "first" child after this marriage, James, arrives in 1850 born in York City - needed to check when he was born (you suggest Feb 1850) as this may explain the speed of the marriage - also there are incomplete records of the parents on the document - they may not have been alive by then ?? the witnesses are also traced in paperwork
I say first child as I tried to find children born to this couple with the names Ellen and Michael Gallagher and I found none!
However I was able to trace an Edward Galaher born on 11 Feb 1849 to a Michael Galaher in Athleague County Rosscommon - about 40 odd miles from where he was raised?? whether this is the correct Edward or pure co-incidence or not I don't know - I searched all possible Edward Galahers born to a Michael Galaher in all of Ireland (and all spellings) from 1834 to 1866 and there are only 4 listed and this is the nearest to the date of the one in the UK census. This is a possible leap I know.
However this Edward Galaher was born to a Michael Galaher on 11th Feb 1849 to a Brigid (Biddy) Branelly and baptised in Athleague Roman Catholic Church in County Rosscommon - date is not clear. The christening was sponsored (godparents) by Honora Kelly and Jas Gallagher.
There is no record of a marriage between these two - Brigid or Biddy was born the same year as the Michael I found at the start: I cannot definitely say it is the same Michael. They did however have a further child born in 1850 a girl Honor. She (or at least a Brigid Brannelly - again I searched all children born to a Brigid Brannelly across 40 years throughout all of Ireland) also had a child with Patrick Kean in 1838 to whom she was married in 1836. whether the marriage survived or he died I do not know. The son was called Patrick as well.
The big leaps really are whether the Michael I initially found was the same one who married Ellen McGlone and also the same one who had two children with Brigid???
My Grandfather remembers stories of his ancestor who came from Ireland leaving on a boat to go to America and not getting any further than Liverpool. A Micheal Galaher born in 1816 (aged 35 when he boarded the boat in 18th May 1850) is listed on the Helen Thompson which set sail for Philadelphia via Liverpool. So this may be how he came to be in the UK for the 1851 census.
He is not listed with Ellen or a child on the boat though.
http://www.immigrantships.net/v13/1800v13/helenthompson18500518.htmlHowever whether I believe he managed to get himself and Ellen, who would already be pregnant and Edward, a child born to another mother to the UK is a bit of a stretch...And probably a little less believable after your discovery of the name Ellen Ford
I tried searching for marriage to Ellen Ford from the age of 16 to the age when he turned up in the UK. But nothing.
However Ford is an interesting name which has been mis-attributed/or variously translated form the Irish equivalent according to some reference documents I have read. It may be a mis-translation as with the mis-spelling of Gallagher, galacher, galaher,Golicher, Golicker, Golisher - (the list is endless).
By the way did you find Ellen and James Golisher and Edward Goligher in the 1891 census!
Anyway that is quite a lot of detail - and makes for a great story! How much we can link all the various references to a michael galaher to the one that turned up in the UK I don't know.
RichS