Statistics for occurrence #1 of “upper Missouri” in article pos=19 of The Daily Dispatch: April 19, 1864., [Electronic resource]:

...his example; but the powerful tribe of Yanktonnais, while they want peace, require that "Uncle Sam" shall not penetrate into their territory, and that steamboats with emigrants shall not navigate the upper Missouri . The refugees, murderers of the lower bands and the evil disposed of other hands, are joining them, preparatory to a spring campaign.
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