As early as 1860, she foresaw the approaching struggle, the Civil War being about to start, and began collecting and preparing articles for hospital use. At the beginning of the war, she cared for sick and wounded soldiers at the Battle of Shiloh at Pittsburg Landing, Tennessee and other battlefield sites. The government placed an ambulance at her command, and during the war she assisted in hospitals in the neighborhood of Washington, at Fredericksburg, Virginia, on the Peninsula, and elsewhere.