Alexander Schimmelfennig was born in Germany in 1824. A graduate of the German military academy he joined Franz Sigel, Carl Schurz, August Willich, Peter Osterhaus, Max Weber in taking part in the failed 1848 German Revolution.
Schimmelfennig emigrated to America and on the outbreak of the American Civil War he joined the Union Army. Commissioned as a colonel he fought under John Pope and Franz Sigel at the second battle of Bull Run (August, 1862). Promoted to brigadier general he took part in the battles at Chancellorsville (May, 1863) and Gettysburg (July, 1863), where he was wounded and cut off from his regiment for three days.
Transferred to the Carolinas, he suffered from ill-health. As well as the effects of the wounds he received at Gettysburg, he contacted malaria. He was commanding the defenses of Charleston when he died of tuberculosis in 1865.