A bill to authorize the acquisition and protection of nationally significant battlefields and associated sites of the Revolutionary War and the War of 1812 under the American Battlefield Protection Program.

Amends the Omnibus Public Land Management Act of 2009 (the Act), with respect to the Battlefield Acquisition Grant Program, to: (1) expand the current definition of "battlefield report" to include the report entitled "Report to Congress on the Historic Preservation of Revolutionary War and War of 1812 Sites in the United States"; and (2) expand the Program to permit the acquisition not only of an "interest in an eligible site," but also an "eligible site."

Requires acquisitions of lands or interests under the Act to be from willing sellers only.

Requires the Secretary of the Interior to submit to Congress a report on related activities, including: (1) preservation carried out at the battlefields and associated sites identified in the battlefield report; (2) changes in their condition; and (3) other relevant developments related to such battlefields and sites.

Authorizes appropriations to the Secretary to provide grants under the Program through FY2019 for the protection of Civil War, Revolutionary War, and War of 1812 battlefields.