During the Gold Rush in San Francisco, miners were asking for sturdy and durable workpants. Levi Strauss made pants from heavyweight denim (from serge de Nimes, a twill made in southern France), which was dyed with indigo – hence the name blue jeans. Indigo was inexpensive and easy to acquire. Also, indigo maintains its color fastness when laundered. Leg openings were wide enough to go over work boots.
