you are really best to seek out records detailing his citizenship. Don't assume they came from Ireland, some landlords shipped their tenants to England or Scotland to get them out of the way. Track down his will, obit, profession and religious affiliations, very important.Where was he buried? Go to Irish records only when you know solid facts, there are very few that are free. For emigration try castle island, the ships list or immigrantships.net. Go to reference library and see if Washington had a city directory for the years leading up to his first appearance. Good luck!