The M1908 was based on a 1904 patent by Mexican Army General Manuel Mondragón. This original design, which had attracted the interest of the Mexican government, could not be produced indigenously as Mexico at that time lacked the manufacturing capacity to produce large quantities of the gun. Looking for a solution, Mondragón initially sold the patent rights to Saint-Chamond in France, where only a few were produced before the rights were shifted to the Swiss arms manufacturer SIG in 1908. Further development of the rifle was undertaken there under the direction of Gotthard End. SIG set up production of the weapon in 1910 and the same year, the Mexican Army ordered 4,000 units. However, ultimately only 300 rifles would be delivered; Mexico's economic situation, plus outbreak of the Mexican Revolution, resulted in the order being cancelled prematurely.
With the remainder of the production left unsold, SIG attempted to market the Mondragón rifle internationally, but achieved few sales until the outbreak of World War I. Many of the unsold rifles were bought by Germany in 1915, who issued them to their air force under the designation Flieger Selbstladekarabiner 1915 (Aircraft Self-Loading Carbine 1915). These rifles were issued with 20-round drum magazines. It was designed to be used by aerial observers against enemy planes, however the introduction of synchronised aircraft machine guns rendered the rifle obsolete in German service and by 1917 it had been retracted from issue.
After World War I, the Mondragón became surplus and therefore many were disposed of, ending up scrapped or sold off. The rifle continued to appear in small numbers during international wars right up until World War II. Whilst they did not produce the weapon anymore, SIG used the Mondragón as the basis for some of their experimental self-loading rifles developed in the 1920s and 30s.
The Mondragón was a gas-operated self-loading rifle that utilised a rotating bolt, which allowed the bolt to be locked into grooves situated on the inside of the receiver. The gas impingement system was a simple tube and piston; the excess gas that would be produced from the ignition of the cartridge would be redirected from the barrel back to the receiver via the gas tube, forcing the bolt backwards.
The rifle was fed from a 10-round fixed box magazine, although experimental detachable magazines were developed. It also included a bipod and adjustable rear tangent sight for long-range shooting. A bayonet could be fitted to the muzzle.
The Mondragón reportedly suffered poor accuracy and was susceptible to dirt and mud, as noted by military observers in Britain, France, and the United States. These shortcomings may have hindered potential sales.