Trench Coats have a military background. They developed from several other coats, such as the serge greatcoats, before being used in the First World War. The name and general style of the coat during this period carried over into civilian use. They are a very useful addition to a suit during some types of extreme weather.
One advantage of the large trench coat is that it can be worn over other clothing without any issues. This is undoubtedly part of the military appeal; a uniform could be kept neat and dry under a trench coat. This also works well for business suits. A trench coat keeps out the weather elements, leaving a suit well protected underneath.
Though often cut in the same way as modern coats the early military coats were often made from cotton. This was inexpensive, durable and treated to be made water resistant. These coats were almost always military khaki in colour.
This was a high end version of the coat. It is waterproof and has a warm silk lining, which is sometime removable. Initially only military officers could wear this, but modern trench coats are only a slight redesign of this classic garment.
This is a modern variation, and probably the hardest wearing type. It is heavier, warmer and more durable than almost any other natural material. It also reasonably easy to maintain, not requiring dry cleaning. Unfortunately these are expensive, and can be associated with the uniform of gangsters and foreign spies. Otherwise, these may catch on as a classic modern alternative.
Modern trench coats are not a loose as old military ones. Their extra warmth means they don’t require additional layers underneath. As such, a trench coat is a useful item for suit owners when they require protection from any wet or cold weather. An umbrella and a good trench coat are all a suit owner need to have on hand. They offer protection and still manage to look quite stylish.