Blue jeans, almost universally shortened to jeans, are the archetypal garment of the twentieth century. The name itself comes from a textile used to make workwear trousers worn by sailors in sixteenth century Genoa, Italy. An inexpensive and sturdy blend of cotton, wool and linen, it was called Génes after the French name for Genoa. Génes was anglicized to jean when the textile was imported to England, where it was widely used and manufactured. Jean evolved and by the eighteenth century was made entirely of cotton and used primarily for workwear. Pants made from jean fabric were commonly referred to as "jean pants," the origin of the contemporary name.
Somewhat confusingly, today's jeans are actually made from denim, a sturdy cotton twill weave textile. More durable than jean fabric, denim might be an anglicized name for a French textile called serge de nîmes. It has also been suggested that a canny eighteenth century British manufacturer applied a French-sounding name to his indigo dyed cotton textile, hoping to improve its prestige.
Denim and the particular style of pants called jeans, relatively slim, ankle-length trousers worn for work or casual dress, converged in the early 1870s. A Nevada tailor named Jacob Davis designed and made a pair of work pants with riveted pockets. The pants, made from blue denim or cotton duck, sold readily. Davis realized that it would be necessary to protect his riveted pockets with a patent, but couldn't afford the $68 application fee. Davis wrote to Levi Strauss, his San Francisco based textile supplier, with a suggestion that Strauss back the patent. Working together, the two businessman applied for a patent for denim "waist trousers" with riveted pockets. The patent was awarded in 1873, and Levi Strauss & Co. began manufacturing the new product. Davis, the actual inventor of waist trousers, oversaw the Levi Strauss & Co. manufacturing facility.