Hi thank you for your message.
Do you know where in Roscommon and Meath John and Mary were born?
When doing genealogy research in Ireland one of hte main pieces of information you need is an exact location-preferably a parish name. Most Irish record sources- church records, land records, census records- are based on specific locations. Until you know a specific location within Ireland, preferably a parish or placename, it may be difficult to do anything more with these records.
Do you have any documentation relating to either of them that mentions a placename such as townland/parish/village/town?
Have you looked into John's emigration to the US, or even his children's emigration? Generally more information was given at the port of arrival rather than that of departure. If you knew what city he arrived in it may be a place to find more information, perhaps even an exact place of origin. Unfortunately, they may have listed England as their palce of origin if this is where they letf from..however it may be worth a try to check anyways.For immigration information in the US go to the following link:
http://www.archives.gov/research/immigration/
Some other websites which you may find helpful are:
The National Archives of Ireland http://www.nationalarchives.ie/genealogy1/genealogy-records/introduction/
The National Library of Ireland http://www.nli.ie/en/family-history-introduction.aspx
The National Archives UK ? genealogy search: http://www.nationalarchives.gov.uk/records/looking-for-person/
The Public Records Office of Northern Ireland http://www.proni.gov.uk/index/family_history.htm
Family Search: https://familysearch.org/
Genealogy Links: http://www.genealogylinks.net/uk/ireland/roscommon/index.html
http://www.genealogylinks.net/uk/ireland/meath/index.html
I hope that this is helpful If you find any more information remember to post it here. The more information you post, the more likely it is that one of our volunteers will be able to advise or assist you. Also include information concerning which sources you may have already used so others may further your search.
Kind regards,
Genealogy Support