Statistics for occurrence #1 of “Armagh” in chapter 45 of Lucius R. Paige, History of Cambridge, Massachusetts, 1630-1877, with a genealogical register:

..., active and faithful friend, a just and generous man, and sincere Christian, etc. Mr. Alden adds, that he was a descendant, according to family tradition, from the learned James Usher, Archbishop of Armagh . If this be true, Hezekiah (1) must have been son or grandson of the Archbishop; but James is not a family name along his descendants so far as I have seen.
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Armagh (United Kingdom) 13 4 1 0 0 user votes
Armagh (Louisiana, United States) 0 0 0 0 0 user votes
Armagh (Pennsylvania, United States) 0 0 0 0 0 user votes

† This entity has been selected by the automated classifier as the most likely match in this context. It may or may not be the correct match.