How does a person search for ancestors if grandfather was an orphan and couldn&#

Question:and I don't know any of his relatives.
He came from Ireland to America by way of Mexico where 2 aunts were born and then they came to USA and dad was born in 1898 in Pennsylvania

How do I even start to search his origin?

Best Answer - Chosen by Asker: and I don't know any of his relatives.
He came from Ireland to America by way of Mexico where 2 aunts were born and then they came to USA and dad was born in 1898 in Pennsylvania

How do I even start to search his origin?

Obtain your Grandfather's death certificate, he may have Naturalization Papers, his marriage certificate, any census info, their may be Passenger lists from ships, military records, if he was a member of a church - they have great records & can fill in the gaps. Research his sisters they might provide the information to help your search.

www.familysearch.org
www.rootsweb.com

Sometimes you cannot find the missing information. Write Ireland and ask them for any help they can give.