Who invented wrist watches?

The wristwatch was invented by Patek Philippe at the end of the 19th century. At the time, it was considered a woman's accessory. It was not until the beginning of the 20th century that the Brazilian inventor Alberto Santos-Dumont, who had difficulty checking the time while in his first aircraft (Dumont was working on the invention of the aeroplane), asked his friend Louis Cartier for a watch he could use more easily. Cartier gave him a leather-band wristwatch from which Dumont never separated. Being a popular figure in Paris, Cartier was soon able to sell these watches to other men. During the First World War, officers in all armies soon discovered that in battlefield situations, quickly glancing at a watch on their wrist was far more convenient than fumbling in their jacket pockets for an old-fashioned pocket watch. As the scale of battles increased, artillery and infantry officers were required to synchronize watches in order to conduct attacks at precise moments, whilst artillery officers were in need of a large number of accurate timekeepers for rangefinding and gunnery. Army contractors began to issue reliable, cheap, mass-produced wristwatches which were ideal for these purposes. When the war ended, demobilized European and American officers were allowed to keep their wristwatches, helping to popularize the items amongst middle-class Western civilian culture.

Note: "Discovered" is used when a thing already exists. For example, the discovery of America.

Note: "Invented" means to create the first one of its kind. The science may have existed before but someone took information, knowledge or skill to create something new. In inventions, the first person to patent is usually named the inventor-- BUT, several people could be independently working on the same ideas which would result in the same or similar item.
The wrist watch was developed by the Swiss watch maker Patek Phillippe in 1860, though at first only women wore them. This evolution came from the watches in small cases that were attached by ribbons to the bodice or skirts.
The man's wristwatch was designed by Girard-Perregaux on request from the German Navy circa 1890.