Statistics for occurrence #1 of “Rockingham” in chapter 23 of George Bancroft, History of the United States from the Discovery of the American Continent, Vol. 5, 13th edition.:

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The repeal of the Stamp Act— Rockingham 's Adminis-Tration continued. on Tuesday, the fourth of February, the party of Bedford and the old ministry of Grenville coalesced with the friends of prerogative to exercise over the colonies...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Rockingham (Virginia, United States) 233 0 31 0 0 user votes
Rockingham (North Carolina, United States) 12 0 10 0 0 user votes
Rockingham (New Hampshire, United States) 5 0 3 0 0 user votes
Rockingham (Georgia, United States) 0 0 0 0 0 user votes
Rockingham (Iowa, United States) 0 0 0 0 0 user votes
Rockingham (Missouri, United States) 0 0 0 0 0 user votes
Rockingham (New Hampshire, United States) 0 0 0 0 0 user votes
Rockingham (New Jersey, United States) 0 0 0 0 0 user votes
Rockingham (Ohio, United States) 0 0 0 0 0 user votes
Rockingham (United Kingdom) 0 0 0 0 0 user votes
Rockingham (Western Australia, Australia) 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.