Re: Montague, Patrick Joseph. b. 1850/1, presumably in Co. Tyrone.
The montague side of my family come from Tyrone and Donegal, in particular strabane, castederg and carncorn.The earliest montague I have was married in Castlederg and his name is actually on his marriage record as McTeague, his father is called John too.He apparently had a brother called william and both were Tailors.
Your montague's may once have been McTeague or a derivative of it.I have had luck with http://www.rootsireland.ie/http://www.rootsireland.ie/ in finding records.The records appear to be on ancestry and family search too but rootsireland appear to be easier to find the records and appear better transcribed.