Using cannabis as a medical treatment dates back thousands of years. But the plant has also been employed for many other purposes. For instance, one of the earliest known woven fabrics was said to be made of hemp. More recently, the original Levi jeans were made out of a tough hemp sailcloth for miners during the California Gold Rush, so that their pockets wouldn't tear when filled with gold.
Nowadays, marijuana is often referred to as a "cash crop," but it was actually legal tender in most of America from 1631 until the early 1800's, and you could supposedly even pay your taxes with cannabis hemp. And years before the "drug war," the US Army and Department of Agriculture promoted a "Hemp for Victory" film in 1942, which encouraged farmers to grow hemp for the war effort, as it could be used to make rope and fibers.
Source: Hemp Facts