Births weren’t registered in Ireland till 1864. Prior to that you need to rely on church baptism records. So you need the person’s denomination and the location. Not all church records have survived and of those that do, not all are on-line.
Statutory registration of all marriages started in 1864, with non RC marriages having been registered since April 1845. So I’d start by trying to locate the c 1880 marriage on the irishgenealogy site that Kilaglassan has listed. If you find it, you should then have a parish and an indication as to denomination to search for baptisms.
If you post the couples names on this site, folk will likely help look for the marriage for you.
Thanks Elwyn.
Have found the following which is of interest -
John Dorrington married Mary Caulford in Dublin South on 18 October 1880.
Church Record - Johannes Dorrington of 6 Upper Bridge Street Dublin married Maria Caulford of 9 Cooke Street on 18 October 1880 at St Audeon Dublin R C.
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Found the Death of a Maria Dorrington in 1880 age 27 in Dublin South.
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Is it possible to buy copies of the Marriage Certificate of John and Mary to establish if this is the right John Dorrington. The guy I'm after was born in 1852 the son of James.
Also the Death Certificate of Maria Dorrington which would clarify if this Maria was the wife of 'my' John Dorrington.
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'My' John D. appears for the first time when he married in 1885 in Hitchen Herts (described as a WIDOWER - son of James.)
On the 1891 1901 census he's living in Leeds - states place of birth as Whittlesea Cambridgeshire.
So I'm trying to link the John D in Leeds with the one who married in Dublin in 1870.
Because I could find no trace of John D before 1885 I assumed he must have changed his name to J D at some point - but if he was in Ireland it would explain a lot. Is there a Whittlesea(y) in Ireland?
Appreciating your help.