Oscar Carl Wilhelm was born in February 1861. He was the son of Oskar (II) and Sofia of Nassau. Prince Carl was Duke of Västergötland
After completing his school exams in 1880, he studied first in Uppsala and then at the Swedish Academy of Military Sciences in 1884-85. For two years he was second-in-command of the Mounted Life Guards, and was nicknamed the Blue Prince in reference to their light blue uniforms.
In 1897 he married Princess Ingeborg of Denmark and the couple had three daughters. All three daughters married in accordance with their station. Margareta became Princess of Denmark, Märta became Crown Princess of Norway, and Astrid became Queen of Belgium. The couple also had a son, Prince Carl Junior.
In 1906, he became Chairman of the Board of the Swedish Red Cross, the international aid work of which brought him world fame. Prince Carl became an honorary Doctor of Medicine in 1917, and an honorary member of the Swedish Society of Medicine in 1921. He retired from the board of the Swedish Red Cross in 1945, whereupon King Gustaf V instituted the Prince Carl Medal for meritorious humanitarian efforts in his honour. The prince died in October 1951.