Although not decisive in a military sense, the Battle of Antietam changed the course of the war by providing President Lincoln the opportunity to issue his preliminary Emancipation Proclamation, thereby adding emancipation to the Union’s war aims. Michael Shiner, an African American employee at the Washington Navy Yard, included the text of Lincoln’s proclamation (possibly written out by his grandson Louis Alexander) in his diary for 1862. For Shiner, himself a former slave, the significance of the proclamation was clear and did not require additional explanation for posterity.