The company was founded by Hellmuth Hirth in 1920 as Hellmuth Hirth Versuchsbau, renamed Leichtmetall-Werke GmbH and finally Elektronmetall GmbH as a manufacturer of light alloy engine components, including parts for aircraft engine components. In 1927, Hirth separated this part of the business, renaming it as Hirth Motoren GmbH, with the remainder becoming Mahle GmbH.
The first Hirth Motoren GmbH engine, the 4-cylinder inverted in-line HM 60, was released in 1931 and was fairly successful. An upgrade in the form of the HM 60R improved efficiency, and was followed by 6, 8 and 12-cylinder versions based on the same machinery. Over the next decade, Hirth became one of Germany's leading aero engine manufacturers.
Following Hirth's death in an aircraft crash in 1938, the Reichsluftfahrtministerium ("Reich aviation ministry") nationalised the company, and in 1941 it was merged with Heinkel to make Heinkel-Hirth. Although the existing engine series were continued, Heinkel also used the Hirth production facilities as a basis for work by Hans von Ohain on a series of jet engines as well under the new name of Heinkel-Strahltriebwerke, although for various reasons none was widely used, through their final Heinkel HeS 011 design, for which only 19 testing prototype powerplants were ever built, and intended for use in a proliferation of German jet combat aircraft design proposals late in the war.
Following World War II, this merger was dissolved, and Hirth was independent once again. Because of the prohibitions on German aviation during the Allied occupation, Hirth manufactured small stationary engines, as well as motors for snowmobiles. Eventually, Hirth returned to aircraft engine manufacturing in 1965, but in 1974 went into voluntary liquidation. The company was acquired by Hans Göbler, who returned it to making small two-stroke engines.
The beginnings of ultralight aviation in the 1980s created another opportunity to re-enter Hirth's original marketplace, and the company has been a notable builder of engines for these aircraft ever since.