Frock coats are knee-length coats historically worn by men. There are two primary styles of frock coats: Victorian or Edwardian period, and Old West — also known as Tombstone. While stylistically similar, the Victorian or Edwardian frock coat is more commonly associated with the term, as it came earlier in history. Basic style appointments include being knee-length, having buttons that run almost the entire length, and being flared at the bottom.
Thought to be initially worn by military men, frock coats are said to be popularized by Prince Albert, husband of Queen Victoria. Originally, the frock coat was worn as the more casual version of the popular dress coat of the early 19th century. At the time, dress coats were also knee-length coats, though they had the trailing tails cut out at the back, while frock coats did not.
For men, a frock coat is traditionally a double-breasted, close-fitted coat that accentuates the waist. Single-breasted frock coats were also sold, though, and are thought to be even more informal. All frock coat lengths reached the knee, give or take a few inches, and buttoned down to the waist. Like many modern formal coat styles, frock coats also included two buttons in the back, which are used simply as decoration. Below the waist, the coat generally took an inverted conical shape, as the skirt gradually flared out over the legs.
As the more fitted, flared frock coat shape persisted decades into the mid 19th century, it became acceptable as formalwear. Along with the frock coat, men wore white shirts and often wore top hats. Additionally, the lapel of the frock coat was a signature of the look — it was generally sewn onto the coat as opposed to sewn from it, as it made the lapel curve more naturally. Also, pockets were not added to the coat until decades after it was first introduced.
In the Victorian and Edwardian periods, frock coats were generally made out of wool in a muted color — black, charcoal, or navy. In modern times, frock coat costumes are often sold in a dramatic crushed velvet material. People that purchase frock coats for formalwear as opposed to costumes often order them in a lighter polyester material.
With Old West frock coats, people often think of Wyatt Earp and Tombstone, Arizona. Movies and actual photographs from the infamous gun fight at the O.K. Corral generally depict Earp and his gang wearing frock coats, or "rifle frocks," of varying lengths and styles. In addition to Earp, other people are often depicted as traditionally dressing in frock coats, including Oscar Wilde, Charles Dickens, and the Teddy Boys — United Kingdom youth who popularized Edwardian-influenced clothing after World War II. The Teddy Boys wore frock coats — or "drapes," as they referred to them — to enhance their personal wardrobes, rather than as a formality.