Occupation of Baltimore by General Butler. Union troops passing down Lee Street, May 12, 1861. Portion of Boston artillery flanked by Infantry of the 6th Mass. regiment to Federal Hill

The New York Public Library states no known U.S. copyright for this item. Pinax admits it as US-PD only because the work predates 1900, making public domain near-certain worldwide; status outside the U.S. is not asserted and reuse elsewhere is the user's responsibility. Credit: From The New York Public Library.