“The first pocket watch was invented by a German watchmaker named Peter Henlein in 1510. By utilizing the recent advancements in mainsprings, Peter was able to create a smaller watch design that was not possible before.”
https://frankenmuthclock.com/blogs/news/the-history-of-the-pocket-watch?srsltid=AfmBOoonqf7jaVL4Z7KbVsbc-8KqOnfxHkMgllg4z1CMF3tFg7nvHLAe
Helein’s first design was egg-like, and it was made to be worn around the neck rather than inside the pocket. At the time, it was considered the smaller form of telling time; its unconventional shape makes it disturbing to wear. This design became known as the Nuremberg egg watch. This watch would pave the way for industrial for pocket watches until their decline in usage in the 19th century, when wristwatches became a more practical way for soldiers during WWI.
The Nuremberg egg watch’s redesign in the 17th century allowed it to fit into the pockets, and aesthetic elements began to play a bigger role in the overall design of future models. Now that their origin has been explained, let’s pass through all the different models and usages for them.