Our immediate neighbor to the south, the Republic of Mexico, has been cursed with internal conflict since gaining independence from Spain in 1821. Repeated attempts at creating a democratic society were frustrated by political and social instability resulting from foreign interventions, revolutions, and Mexican army coups — tempered by periodic bouts of bankruptcy.
As were many Latin American countries, Mexico was heavily in debt to European nations and in 1862 French, British and Spanish troops occupied Mexico's ports until payment was made. The United States, embroiled in its own civil war, was unable to prevent intervention but under diplomatic pressure, the British and Spanish eventually withdrew their troops.
The French, meanwhile, decided this would be an perfect opportunity to create a sphere of influence in the Western hemisphere. They deposed the Mexican president, Benito JuÃ¡rez, and set up a puppet "emperor" in the person of an Austrian archduke, Ferdinand Maximilian. Needless to say, except for a small group of wealthy sycophants and army officers, Maximilian had little support among the Mexican populace and only maintained power thanks to a contingent of the Légion étrangÃ¨re (Foreign Legion).
With the end of our fraternal conflict, the U.S. began clandestinely supplying Juarez's Mexican army with weapons. While most were surplus rifled muskets, quantities of Model 1865 Spencer repeating carbines were also obtained. Through commercial sources (a.k.a. gun runners) the JuÃ¡ristas also obtained numbers of Henry and Winchester Model 1866 repeating rifles and carbines. These lever-action repeaters quickly became as popular south of the Rio Grande as they did in "El Norte."
56-50 Spencer - consisted of a copper, rimfire case 26mm long loaded with 45 grains of black powder and a 350-grain lead bullet. While ballistically unimpressive, the seven-shot Spencers provided the peon soldier with firepower far superior to that of his French foes.
.44 Henry - both the Henry and Winchester used a rimfire cartridge a copper case 23mm long topped with a 200-grain flat-nosed lead bullet that 28 grains of black powder drove to approximately 1,200 feet-per-second.
Nationalist forces under JuÃ¡rez and Porfirio DÃaz battled the French occupiers and in 1867, at the Battle of Puebla, defeated Maximilian's forces and captured Mexico City and the erstwhile emperor — who was executed.
With the execution of the emperor, Mexico once again became a republic with JuÃ¡rez as president. But after the euphoria of the revolution faded, the traditional animosities between the army, church, and hancendados (large landowners) and the masses of poor campesinos, peons and Indians led to increasing discontent. 
In the early 1870s, in an attempt to upgrade the army's equipment, the Mexican army purchased surplus U.S. Model 1870 "Trapdoor" Springfield rifles. Remington and the Whitney Firearms Company both produced a special versions of their Rolling Block carbine that had a movable firing pin that permitted the use of either the .50-70 or the 56-50 Spencer cartridge. 
In the 1880s, surplus U.S. Navy Model 1870 Rolling Block rifles in .50-70 were also acquired. According to George Layman, Rolling Block rifles in American military calibers remained very popular in Mexico for quite some time, which was probably a result of their closeness to the U.S. and the availability of inexpensive surplus ammunition. 
.50-70-450 USS - this cartridge was based on a straight-walled, rimmed case 1.8 inches (46mm) long which contained 70 grains of black powder and a 450-grain lead bullet. Muzzle velocity was in the area of 1,490 fps.
Among the weapons purchased by the Mexican army during this period were numbers of Spanish pattern M1870 Remington, Whitney Type II Rolling Block and Peabody rifles chambered for the .43 Spanish cartridge.
11mm Cartucho para Remington - as the .43 Spanish is known in Latin America, it used a rimmed, bottlenecked case 57mm load topped with a 375-grain lead bullet and 78 grains of black powder with a muzzle velocity of 1,380 fps.
Benito Juarez died in 1872 and was succeeded — with the Mexican army's backing — by Porfirio Diaz who declared himself "president," although, in reality, he would be the dictator of Mexico for the next thirty-nine years.
DÃaz welcomed foreign investors who soon controlled Mexico's railroads, mines, ports, agriculture, cattle, petroleum and other industries. DÃaz's cronies in the bureaucracy, business community and army accumulated wealth and influence, while in rural areas, hacendados expropriated land from the campesinos who then became peons.
DÃaz addressed the problem of internal security by hiring bandit gangs and forming them into the Rurales (Rural Police), a paramilitary force that was better trained and paid than many of the Mexican army's unenthusiastic conscripts. Not only was banditry reduced, but the Rurales also served as an effective force against the periodic peasant uprisings and labor strikes.
Between 1881 and 1887, Winchester supplied the Mexican army with their Model 1879 Hotchkiss, a bolt-action, five-shot repeating carbine chambered for the .43 Spanish cartridge. Sufficient Hotchkiss carbines were purchased to equip two regiments of elite cavalry and the Presidential guard. At the same time, they purchased 1,000 Winchester Model 1873 carbines for issue to the Policia Federales (Federal Police).
.44 Largo - as the.44 WCF was known throughout Latin America. This cartridge had a rimmed, straight-walled case loaded with a 200-grain flat point, lead bullet that a charge of 40 grains of black powder drove to approximately 1,325 fps.
In 1888 the Mexican government purchased 100 Model 1883 Hotchkiss rifles from Winchester. As the U.S. army upgraded their weaponry in the 1890s, surplus Model 1873, 1879 and 1884 "Trapdoor" Springfield rifles and carbines began to appear in Mexico and saw service as late as the 1911 revolution (see below).
.45-70-405 USS - the Trapdoors' cartridge consisted of a rimmed, straight-walled case 2.1 inches (53mm) long, loaded with a 70-grain charge of black powder that propelled its 405-grain lead bullet to 1,315 fps. 
As the U.S. government became discontented with the Diaz regime, the Mexican army began to look overseas for sources of weapons. One of the first trans-Atlantic purchases was a small quantity of gas-sealed revolving carbines made by Fabrique d'Armes Henri Pieper of Liege, Belgium and which were issued to the Presidential guard. Based upon Pieper's gas seal revolver (some of which the Mexicans also purchased) the so-called Carabina Mexicana Modelo 1893 had a seven-shot cylinder, double-action trigger, external hammer and full-length stock.
8mm Pieper - a rimmed cartridge with a tapered case 41mm long containing a 125-grain lead bullet seated completely inside the case. When the carbine's hammer was cocked, the cylinder was moved forward and the case mouth inserted in the barrel. Upon firing it expanded and formed a gas seal. Both black and smokeless powder loads were manufactured and late production cartridges were loaded with full-metal-jacketed (FMJ) bullets.
Disillusioned provincial leaders and intellectuals formed the Anti-Reelectionist Party headed by Francisco Madero. In 1910, the 80-year-old DÃaz ran for reelection, and Madero announced he would run in opposition on a platform of agrarian reform and democracy. Madero won the election and DÃaz ordered him imprisoned, but Madero managed to flee to Texas and organized a revolt which quickly gained support among much of the population.
In the northern state of Chihuahua, a former horse thief, José Doroteo Arango ArÃ¡mbula — better known as Pancho Villa — formed an irregular cavalry force, la DivisiÃ³n del Norte (Division of the North), to support Madero. Indians and peons in Puebla, Morelos and Chiapas, were led by the charismatic Emiliano Zapata whose Ejército Libertador del Sur (Southern Liberation Army) also declared for Madero.
On November 20, 1911, Villa and Madero's Mexican army inflicting a crushing defeat upon DÃaz at the Battle of Ciudad JuÃ¡rez. DÃaz fled the country and Madero was "reelected" president in November of 1911.
I would like to thank Lou Behling, George Hoyem, Dan Reynolds, Garry James, Keith Doyon, George Layman, Roy Marcot, David Squiers, and Herbert House for supplying materials used to prepare this article.
 A campesino was a rural farmer who sometimes owned his land or worked as a sharecropper . Peons were tied to the land by debt and tradition and were considered the "property" of the hacienda they lived and worked on.
 Layman, George. Remington Rolling Block Military Rifles of the World. Andrew Mowbray Publishers, Woonsocket RI. Pages 188 & 192.
 Ibid. Pages 187-188.
 Whitney Type II carbines in .45-70 were also purchased by the Mexican government.