Although wristwatches were first made for women, they've been made in a variety of styles and materials for men since World War I and have been one of the most (if not the most) popular fashion accessory among men for decades.
During World War I, Cartier introduced a watch that began to make wristwatches for men commonplace. Tired of using pocket watches, pilot Santos Dumont wanted an easier-to-use wristwatch, so he contacted Cartier and the Santos wristwatch was born. Shortly after its inception, the Santos became available for general sale. Since then, just about every wristwatch manufacturer has made watches for men, from Omega to Patek Philippe to Rolex.