The company began in 1873, formed by Charles Alfred Hahn and his brother Aimé Auguste Hahn, and called Charles Hahn & Cie. After the death of Charles Alfred in 1875, the company became known as Hahn Frères et Cie. They produced watches and watch movements as early as 1883 and won medals at Paris in 1878, La Chaux-de-Fonds in 1881, Geneva in 1896, and a gold medal in Paris in 1900 for their work.
Charles Hahn (son of the founder) had taken charge of the company by 1898, with it then known as Charles Hahn & Cie. The company was a maker of ebauches and a finisher of movements and watches and could produce simple or complicated watches in Landeron. The company was producing chronograph movements by 1923 and acquired the patents of Anatole Breitling in 1924. The company's growth lead many people to refer to it simply as Landeron by the 1910s.
In 1925, Landeron merged with Fabrique d'Horlogerie de Fontainemelon (FHF), being renamed Fabrique d'Horlogerie de Fontainemelon, succursale du Landeron ci-devant Charles Hahn & Cie (“Landeron branch under Charles Hahn”). FHF/Landeron became a founding member of Ebauches SA in 1926.
Landeron's column wheel chronograph movements were famous, and the company supplied these movements to many militaries. Examples include Cal. 11 and 13 and the state-of-the-art Cal. 39. Because they held the Breitling patents, Landeron was the exclusive supplier of column wheel chronograph movements until their expiration in the 1930's.
Just before World War II, Landeron developed the first cam actuated chronograph. Their Cal. 47 had three pushers One to start, another to stop, and a third to reset the counter. They refined this movement to become the two-pusher Cal. 48. This would become one of the most popular chronograph movements ever made, with more than 3.5 million examples produced between 1937 and 1970. The lower price of production compared to a column wheel model meant an average person could afford a chronograph for the first time.
In the 1960's, Landeron produced the first Swiss electric movement, Cal. 4750. It featured a battery-powered balance wheel rather than a mainspring.