There were over 75 raids and battles that took place in Maryland during the Civil War, including Bloody Antietam--the bloodiest day in American military history. As a border state between the North and South during the Civil War, Maryland's loyalties were strong for both sides. The first casualties of the war occurred during the Baltimore Riot of April 19, 1861, when members of the 6th Massachusetts Regiment were attacked by Confederate supporters while traversing through the city on their way to protect Washington, DC, from attack. Ten days later, Maryland chose not to secede from the Union by a vote of 53-13. On September 17, 1862, near Sharpsburg, one of the largest and bloodiest battles of the Civil War took place at Bloody Antietam. At the end of the day, nearly one in four men would be a casualty of the battle, making it the bloodiest day in American military history. There were over 75 skirmishes, raids, and major battles that took place in Maryland during the Civil War. Through vintage photographs, Maryland in the Civil War shares the state's rich military heritage.