Leonidas was a Swiss luxury watch brand founded in 1841 by Julien Bourquin in Saint-Imier, Switzerland. The company became known for producing high-quality, reliable timepieces and gained a reputation as one of the premier watch brands in the world. In 1886, Ferdinand Bourquin took over the family business and expanded the company, selling watches to the Russian aristocracy and establishing the brands La Populaire and Léonidas. The company produced stopwatches, chronographs, and a variety of wrist watches. In 1911, Leonidas faced financial difficulties and was liquidated, but it was later acquired by Constant Jeanneret-Droz and merged with Heuer in 1964. The brand was retired after the company became TAG Heuer in 1985. Today, Leonidas is remembered for its commitment to innovation and craftsmanship, and its vintage timepieces are highly sought after by collectors and watch enthusiasts.