Militias and the People's Army of the Republic

Battalions were the basic unit of militias. They were created on the initiative of civilian, party, syndicate, and military volunteers and were quite well organized. They were all structured in the same way, with a political and military command, and little in the way of training.

Women were required to take the place of workers who had to answer the call from their syndicates and parties to form militia battalions. They took over many of their tasks, including farming, which was crucial for sustaining the population.

The tensions in the first few months of the war, with a nonexistent Republican military force and political parties in control of militia units, made it impossible to unify and form a regular army.

Stemming from the Antifascist Worker and Peasant Militias (Milicias Antifascistas Obreras Campesinas), the Fifth Regiment was formed after the coup, made up of militias under the leadership of the Communist Party of Spain (PCE). Due to its importance and size, it eventually became a legitimate training and command center.

The Fifth Regiment seeded numerous battalions and companies that would eventually form the People's Army of the Republic, including those known as the Compañías de Acero (Steel Companies). In October 1936, it became the First Mixed Brigade (Primera Brigada Mixta), a basic unit of the new People's Army.

In order to gain more effective control of this amalgamation of forces, the Inspectorate General of Militias was created in August 1936. Its tasks included managing the flow of materials so that forces were more or less equally equipped.

With the arrival of Francisco Largo Caballero in government, in September 1936, it became possible to start forming a regular army, with marine and air divisions under the command of Indalecio Prieto Tuero, and with José Asensio Torrado in charge of organizing the army. It also had the support of the political forces of the Popular Front (Frente Popular).

In June 1937, the Spanish Republican Army (Ejército de la República Española) had already been formed and faced its first acid test: the Battle of Brunete in Madrid. In 1938, with the addition of the Quinta del Biberón (or Baby-Bottle Draft, since it was formed of young, new soldiers), the army reached the peak of its development, just in time for the Battle of the Ebro.

Officer courses lasting 15 days were established to address the lack of trained officers in the Republic. These were replaced by what were known as People's War Schools (Escuelas Populares de Guerra) in December 1936.