Statistics for occurrence #1 of “Wilderness, Va.” in chapter 75 of Thomas Wentworth Higginson, Massachusetts in the Army and Navy during the war of 1861-1865, vol. 1, Mass. officers and men who died.:
... Md.,July 8, 1863.
O'Loan, Michael, Corp.,16th Mass. Inf.,Chancellorsville, Va.,May 3, 1863.
O'Malley, Owen,7th Mass. Inf.,Marye's Heights, Va.,May 3, 1863.
O'Neil, James, 2d Lieut.,9th Mass. Inf., Wilderness, Va. ,May 9, 1864.
O'Neil, James,7th Mass. Inf.,Marye's Heights, Va.,May 3, 1863.
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