Statistics for occurrence #1 of “Washington, D. C.” in entry buchanan-robert-christie of Harper's Encyclopedia of United States History:
...th Mexico: and was made a lieutenant-colonel in 1861.
He served in the Army of the Potomac continually during the Civil War, and was brevetted major-general United States Army in 1865.
He died in Washington, D. C. , Nov. 29, 1878.
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