Marie Brose was born on August 24, 1834 in the village of Brest, France. Her mother was French and her father Turkish. After the death of her father when she was about ten years old, young Marie immigrated to America. Around the age twenty, she married Bernard Tepe, a tailor from Philadelphia.

At the start of the Civil War, Bernardo enlisted in Company I, 27th Pennsylvania Volunteers. He desired for his wife to stay home and manage their small tailor shop, but Marie refused to stay behind. She followed her husband to war and was attached to the 27th PA. She left the 27th and served as a Vivandiere to the 114th PA. Her uniform was similar to that of the women who followed the eagles of France. She wore a blue zouave jacket, a short skirt trimmed with red braid, which reached to just below the knees, and red trouseres over a pair of boots. Marie also wore a man's sailor hat turned down.

Known throughout the Union Army as "French Mary" she fought and ministered to the needs of the wounded. A brave and fearless woman, she saw action at Fredericksburg and Chancellorsville. After the battle on May 3, 1863 at Chancellorsville, Marie received the "Kearny Cross" for helping to organize one of the field hospitals. Marie was with her regiment in the campaign up to Gettysburg. In the spring of 1864 Marie was seen at the Bloody Angle during Spotsylvania by a soldier from another regiment.

After the war, Marie moved to the Pittsburgh area and maried Richard Leonard, a veteran of Company K, 1st Maryland Cavalry. Their date of marriage was April 9, 1872. She died in 1901 and is buried in St. Paul's Cemetery, Lafferty Hill, Baldwin Borough, PA