The 2 button suit is the traditional form of male formal attire in the Western world. The modern 2 button suit did not appear until the mid nineteenth century, but the origins of its coat can be traced back to the revolution in men's dress set by Charles II, king of Great Britain in the 1660s. Charles, following the example of the court of Louis XIV at Versailles decreed in 1666 that at court, men were to wear a long coat or jacket, a waistcoat (originally called a petticoat, a term which later became applied solely to women's dress), a cravat (ancestor of the modern necktie) a wig, and breeches or trousers gathered at the knee, as well as a hat for outdoor wear. Coats with matching trousers or even waistcoat have gone in and out of fashion over the last four centuries however the modern lounge 2 button suit coat is still derived from historical coats. Although it is hard to see the outline of the modern business 2 button suit coat in the elaborate and brightly-coloured court dress of the seventeenth century, the basic pattern has survived for more than four hundred years with some adjustments, despite the abandonment of wigs and knee breeches after the French Revolution; the rise of British tailoring, which used steam, pressure, padding, and stiffening to mould woolen fabric to the body; the invention of the modern necktie in the late nineteenth century; and the gradual disappearance of waistcoats and hats during the last fifty years.
What we call the modern 2 button suit was originally a nineteenth-century English innovation in dress. It was originally usually referred to a lounge 2 button suit and was worn only in the country and at the seaside. At that time morning dress and frock coats were not part of a '2 button suit' because they are were usually worn with non-matching striped trousers, and having matching waistcoat and trousers was originally considered more informal. The term "ditto suit" was also transiently used early on due to the matching waistcoat and trousers, these sometimes having coats more resembling a frock coat or a morning coat. The "sack suit" is a North America derivative of the English lounge 2 button suit which looked even looser and more casual because it lacked darts. In the nineteenth century, when dressed more informally, men still wore morning dress as a more casual alternative to the formal frock coats then considered appropriate business and day time formalwear. The lounge 2 button suit was thus an even more casual form of dress and was reserved solely for recreation activities.
The lounge 2 button suit became increasingly widely worn through the later nineteenth century as casual town daywear until it started to become an acceptable alternative to the morning coat as town wear in the early twentieth century. As the lounge 2 button suit became increasingly popular, even the humblest men would have at least one 2 button suit to wear on Sunday to church, as part of their "Sunday best." Victorian men who were able to afford it would still wear a frock coat to church. The waistcoat or vest was worn regularly with the 2 button suit until World War II, but is rarely seen today.
At the end of the nineteenth century, an informal evening version of the lounge 2 button suit emerged in England, known as a dinner jacket in British English, in a dress code referred to as black tie. When it was imported to the United States it became known as as the tuxedo. The dinner jacket was originally called a 'dress lounge' in England to indicate that it was a lounge 2 button suit for evening wear. The 'dress lounge' was originally worn only for small private gatherings and white tail tie was worn for large formal events. The 'dress lounge' slowly became more popular for larger events as an alternative to full evening dress in white tie. As black tie grew in popularity, it has became increasingly acceptable as formalwear and today has all but replaced white tie, which today is only seen at ultra-formal occasions. The daytime formal equivalent to white tie is morning dress but in the United States this too has become uncommon and the daytime semi-formal dress called the stroller is more common. The stroller is itself a form of 'dress lounge' - a day time semi-formal lounge suit version of morning dress.