Little is known of the early life of Agnes Salm-Salm. Many scholars believe that she worked in a circus, then as an actress in Cuba. In she returned to the United States but soon left her home in Vermont to visit her sister in Washington, D.
She had been riding her horse one morning through the city when Felix first saw her and he made sure she was invited to a party that he would be attending.
Soon Felix proposed to her and they were married on August 30, , despite opposition from her family he was Catholic and she was Protestant.
Prince Felix had a post as adjutant of Louis Blenker in the Army of the Potomac , and soon proceeded to the front. Agnes could not be apart from Felix for too long and eventually followed him to the battlefield. At his camp she would care for the sick and wounded soldiers although she had no previous knowledge of medicine. For four years she traveled with the troops through war-torn Virginia. As the wife of a colonel she had access to supply wagons and luggage meant for the officers and would often steal supplies in order to care for the soldiers.
This sparked a controversy that President Abraham Lincoln eventually settled; the President also pinned a captain's star on her at the time. In January the troops were ordered to go to Aquia Creek , Virginia, and of course Agnes followed her husband. Here she made a bet that she would give President Lincoln three kisses within the next few days on his visit to the camp, and she succeeded in doing so.
