What is a "surtout"?

A surtout is a type of overcoat that was popular for men's formal wear in the 18th and 19th centuries. It was usually made of wool and reached down to the ankles, with a fitted waist and flared skirt. The coat typically had a high collar that could be turned up to protect the neck and ears from the wind. Surtouts were often worn over a suit or evening wear and were designed to provide warmth and protection from the elements while maintaining a stylish and sophisticated appearance.