Comment by forinti

AFAIK, wrist watches were an idea by Santos Dumont, because he needed something practical during flight. He asked his friend Louis Cartier to come up with something and hence the first one was invented in 1904. It became popular (among rich people, I'm sure) in 1911 when Cartier started selling them to the public. I knew the bit about Dumont needing to keep time without using his hands, the rest I looked up just now.