In August 1936 Harry Pollitt arranged for Tom Wintringham to go to Spain to represent the CPGB during the Civil War. While in Barcelona he developed the idea of a volunteer international legion to fight on the side of the Republican Army. He wrote: "You have to treat the building of an army as a political problem, a question of propaganda, of ideas soaking in."
On 10th September 1936 Wintringham wrote to Harry Pollitt that he had arranged for Nat Cohen, a Jewish clothing worker from Stepney, to establish "a Tom Mann centuria which will include 10 or 12 English and can accommodate as many likely lads as you can send out... I believe that full political value can only be got from it (and that's a lot) if its English contingent becomes stronger. 50 is not too many."
Maurice Thorez, the French Communist Party leader, also had the idea of an international force of volunteers to fight for the Republic. Joseph Stalin agreed and in September 1936 the Comintern began organising the formation of International Brigades. An internatinal recruiting centre was set up in Paris and a training base at Albacete in Spain.
Wilfred Macartney, one of the few volunteers who had military experience, he was appointed the first commander of the British Battalion in December 1936. According to Jason Gurney: "it soon became evident that he (Macartney) had very little idea of the duties of a Battalion Commander." Peter Kerrigan added: "He was not terribly popular in the battalion but I think he was respected for his ability. He was a capable military officer. He had a rather arrogant style."
The British Battalion also had a political commissar. The first person to hold this post was Dave Springhill. He was replaced in February 1937 by George Aitken. Later this position was held by Harry Dobson and Wally Tapsell.
It was decided by Harry Pollitt, the leader of the Communist Party of Great Britain that Wilfred Macartney should be recalled to London and that he should be replaced by party member, Tom Wintringham. On 6th February, 1937, Peter Kerrigan went to see McCartney. Kerrigan later recalled what happened during this meeting: "I visited him in his room before he went back to have a talk with him about the situation with the battalion and so on. It was the intention that he would come back. This was about mid-January but he had a big, heavy revolver and I had a rather small Belgian revolver, and he said: Look Peter, how about you giving me your revolver. I am going through France I don't want to lump this thing about. I said all right. He asked to show me how to operate it. I took the revolver in my hand but I can't say for sure whether or not I touched the safety catch, or whether it was off or not, or whether I touched the trigger, but suddenly there was a shot and I had hit him in the arm with a bullet from the small Belgian revolver. We rushed him to hospital, got him an anti-tetanus injection and he was patched up and off he went."
Tom Winteringham now became the commander of the British Battalion. British Battalion of the International Brigade. The commissar for English-speaking volunteers in the battalion, Peter Kerrigan, wrote to Wintringham about the standard of the soldiers under their control: "Some lads have no desire to serve in the army. All recruits must understand they are expected to serve. Tell them; this is a war and many will be killed. This should be put brutally, with a close examination of their hatred of fascism. A much greater discipline is needed. Recruits must be told there is no guarantee of mail and the allowance is only three pesetas a day." Wintringham agreed with Kerrigan and sent a message to Harry Pollitt: "About ten percent of the men are drunks and flunkers. I can't understand why you've sent out such useless material. We call them Harry's anarchists."
After failing to take Madrid by frontal assault General Francisco Franco gave orders for the road that linked the city to the rest of Republican Spain to be cut. A Nationalist force of 40,000 men, including men from the Army of Africa, crossed the Jarama River on 11th February.
General José Miaja sent three International Brigades including the Dimitrov Battalion and the British Battalion to the Jarama Valley to block the advance. On 12th February, at what became known as Suicide Hill, the Republicans suffered heavy casualties. Tom Winteringham, the British commander, was forced to order a retreat back to the next ridge. The Nationalist then advanced up Suicide Hill and were then routed by Republican machine-gun fire.
On the right flank, the Nationalists forced the Dimitrov Battalion to retreat. This enabled the Nationalists to virtually surround the British Battalion. Coming under heavy fire the British, now only 160 out of the original 600, had to establish defensive positions along a sunken road. During the afternoon Jason Gurney had been ordered by Wintringham to reconnoitre to the south of the sunken road: "I had only gone about 700 yards when I came across one of the most ghastly sights I have ever seen. I found a group of wounded (British) men who had been carried to a non-existent field dressing station and then forgotten. There were about fifty stretchers, but many men had already died and most of the others would be dead by morning. They had appalling wounds, mostly from artillery."
On 13th February, 1937, Tom Winteringham was hit in the thigh while trying to organise a bayonet charge. Jock Cunningham replaced him as commander.On 8th May, 1937, Cunningham reported to Harry Pollitt: "I am pleased to say that everything is showing marked improvements, discipline is tightening up." Walter Greenhalgh later claimed that Cunningham "was a very good inspiration within a small unit like a battalion, but when they put him in charge of larger units it didn't work out." Fred Copeman was more complimentary describing "Jock Cunningham was the best". Cunningham was himself hospitalised on 15th March and the command went to Copeman.
On 6th July 1937, the Popular Front government launched a major offensive in an attempt to relieve the threat to Madrid. General Vicente Rojo sent the International Brigades to Brunete, challenging Nationalist control of the western approaches to the capital. The 80,000 Republican soldiers made good early progress but they were brought to a halt when General Francisco Franco brought up his reserves. Fighting in hot summer weather, the Internationals suffered heavy losses. Three hundred were captured and they were later found dead with their legs cut off. All told, the Republic lost 25,000 men and the Nationalists 17,000. George Nathan, Oliver Law, Harry Dobson and Julian Bell were amongst those killed during the battle.
After the fighting at Brunete, Jock Cunningham, George Aitken, Wally Tapsell and Fred Copeman were called back to England to have a meeting with Harry Pollitt. Tapsell was highly critical of Aitken and Cunningham. He claimed that "Aitken's temperament has made him distrusted and disliked by the vast majority of the british battalion who regard him as being personally ambitious and unmindful of the interests of the battalion and the men." He added that Cunningham "fluctuates violently between hysterical bursts of passion and is openly accused by Aitken of lazing about the Brigade headquarters doing nothing."
According to Richard Baxell, the author of the British Volunteers in the Spanish Civil War (2007) "they (Cunningham, Aitken, Tapsell, Copeman) were all hauled over the coals by Harry Pollitt for the internal divisions which had been causing great unrest at both battalion and brigade level since Brunete." As a result of these discussions Cunningham and Aitkin were kept back in London whereas Tapsell and Copeman were returned to the front-line.
The author of Homage to Caledonia (2008) has pointed out: "At its conclusion, Pollitt told Aitken, Cunningham and Bert Williams (a political commissar with the Abraham Lincoln Battalion) to remain in Britain, while Fred Copeman (commander of the British Battalion) and Tapsell were to return to Spain. Fred Copeman later commented: "His (Pollitt) proposal was that we return to Spain and everybody else remained where they were. Jock just broke down. I have never seen anything like it. I tried to help him out but it was no good." Jock Cunningham was so angry he immediately resigned from the Communist Party of Great Britain.
The British Battalion were responsible for capturing Purburell Hill at Quinto (August 1937). They also suffered high casualties defending Teruel in 1938 and Ebro (July/August 1938). It is estimated that of the 2,000 soldiers in the British Battalion, 500 were killed and 1,200 were seriously wounded.
Men from Britain who fought with the Republican Army included George Orwell, Christopher Caudwell, Jack Jones, Tom Winteringham, Harry Dobson, Fred Copeman, George Aitken, William Ball, Clem Beckett, William Briskey, Christopher Caudwell, John Cornford, John Dunlop, Bob Edwards, Josh Francis, Tom Murray, Joe Garber, Lou Kenton, Bill Alexander, David Marshall, Alfred Sherman, Ralph Fox, Harry Fry, Jason Gurney, Jack Jones, John Bosco Jones, Peter Kerrigan, Bernard Knox, Wilfred Macartney, George Nathan, Bert Overton, Esmond Romilly, Sam Russell, Hugh Slater, Bob Smillie, Dave Springhill, Wally Tapsell, Tom Wintringham and Sam Wild.
On 25th September 1938, Juan Negrin, head of the Republican government, announced for diplomatic reasons that the International Brigades would be unilaterally withdrawn from Spain. However, General Francisco Franco failed to reciprocate and German and Italian forces remained to continue the struggle.
Before leaving for home Sam Wild, commander of the British Battalion, was quoted as saying: "The British Battalion is prepared to carry on the work begun here to see to it that our 500 comrades who sleep for ever beneath Spanish soil shall serve as an example to the entire British people in the struggle against fascism."