Formation and recruitment
A unit of the Bulgarian International Brigade, 1937
Flag of the Hungarian International Brigades.
Using foreign Communist Parties to recruit volunteers for Spain was first proposed in the Soviet Union in September 1936—apparently at the suggestion of Maurice Thorez—by Willi Münzenberg, chief of Comintern propaganda for Western Europe. As a security measure, non-Communist volunteers would first be interviewed by an NKVD agent.
By the end of September, the Italian and French Communist Parties had decided to set up a column. Luigi Longo, ex-leader of the Italian
Communist Youth, was charged to make the necessary arrangements with the Spanish government. The Soviet Ministry of Defense also helped, since they had experience of dealing with corps of international volunteers during the Russian Civil War. The idea was initially opposed by Largo Caballero, but after the first setbacks of the war, he changed his mind, and finally agreed to the operation on 22 October. However, the Soviet Union did not withdraw from the Non-Intervention Committee, probably to avoid diplomatic conflict with France and the United Kingdom.
The main recruitment centre was in Paris, under the supervision of Soviet colonel Karol "Walter" Świerczewski. On 17 October 1936, an open letter by Joseph Stalin to José Díaz was published in Mundo Obrero, arguing that victory for the Spanish second republic was a matter not only for Spaniards, but also for the whole of "progressive humanity"; in short order, communist activists joined with moderate socialist and liberal groups to form anti-fascist “popular front” militias in several countries, most of them under the control of or influenced by the Comintern.
Entry to Spain was arranged for volunteers: for instance, a Yugoslav, Josip Broz, who would become famous as Marshal Josip Broz Tito, was in Paris to provide assistance, money and passports for volunteers from Eastern Europe. Volunteers were sent by train or ship from France to Spain, and sent to the base at Albacete. However, many of them also went by themselves to Spain. The volunteers were under no contract, nor defined engagement period, which would later prove a problem.
Also many Italians, Germans, and people from other countries joined the movement, with the idea that combat in Spain was a first step to restore democracy or advance a revolutionary cause in their own country. There were also many unemployed workers (especially from France), and adventurers. Finally, some 500 communists who had been exiled to Russia were sent to Spain (among them, experienced military leaders from the First World War like "Kléber" Stern, "Gomez" Zaisser, "Lukacs" Zalka and "Gal" Galicz, who would prove invaluable in combat).
The operation was met with enthusiasm by communists, but by anarchists with skepticism, at best. At first, the anarchists, who controlled the borders with France, were told to refuse communist volunteers, but reluctantly allowed their passage after protests. A group of 500 volunteers (mainly French, with a few exiled Poles and Germans) arrived in Albacete on 14 October 1936. They were met by international volunteers who had already been fighting in Spain: Germans from the Thälmann Battalion, Italians from Centuria Gastone Sozzi and French from
Commune de Paris Battalion. Among them was British poet John Cornford. Men were sorted according to their experience and origin, and dispatched to units.
In 30 May 1937, the Spanish liner Ciudad de Barcelona, carrying 200–250 volunteers from Marseille to Spain, was torpedoed by a Nationalist submarine off the coast of Malgrat de Mar. The ship sunk and up to 65 volunteers are estimated to have drowned.
Albacete soon became the International Brigades headquarters and its main depot. It was run by a troika of Comintern heavyweights: André Marty was commander; Luigi Longo (Gallo) was Inspector-General; and Giuseppe Di Vittorio (Nicoletti) was chief political commissar.
The French Communist Party provided uniforms for the Brigades. They were organized into mixed brigades, the basic military unit of the Republican People's Army. Discipline was extreme. For several weeks, the Brigades were locked in their base while their strict military training was under way.