Thälmann Battalion The Thälmann Battalion was a battalion of the International Brigades in the Spanish Civil War . It was named after the imprisoned leader Ernst Thälmann ( born 16 April 1886 , executed 18 August 1944 ) and included approximately 1 , 500 people , mainly Germans , Austrians , Swiss and Scandinavians . The battalion fought in the defence of Madrid . Amongst the commanders of the battalion were the German writer , historian and World War I officer Ludwig Renn ( later Chief of Staff of the XI International Brigade ) and Prussian World War I officer Hans Kahle , later promoted to lead the Republican 45th division for a time . The battalion , like the International Brigades in general , also attracted its share of intellectuals , such as the well - known writer Willi Bredel who became its commissar . Volunteers . The German - speaking battalions were one of the first and eventually largest groups that formed in the International Brigades , coalescing out of the ' Thälmann Centuria ' of the early war days . Most of the Germans volunteering were working - class people , " members of the Weimar Republic ' s ' lost generation ' , who had never known stability or regular employment " , and to many , the simple arrival in Spain ( through the French blockade ) to join the fight on the Republic ' s side was their first victory after years of losing their political struggle at home . In their home countries of Germany and Austria , fascism had already conquered , giving their foreign struggle a special grim context . As Robert G . Colodny writes in " The International Brigades " : John Cornford , an English communist and poet , echoed these thoughts , describing the Germans as : Ernest Hemingway went even further in his admiration , calling them representative of the " true Germany " and contrasting them unfavourably with the Germans fighting on the other side in the Legion Condor . The respect with which the Germans were accorded - by the others in the International Brigades , as well as by the Republican populace - lifted their spirits as well . Many of them had been stripped of their nationality by the Nazis , and had spent years underground or in exile , and the war gave them the opportunity to reclaim an anti - fascist identity , their vision of a better Germany . For many it was also a time of either communist re - affirmation or political enlightenment ( the largest block of all volunteers in the International Brigades was communist or had been recruited by communists ) . However , the German volunteers were not above human faults and despair - especially as the war dragged on , and got increasingly difficult for the Republican side , which lacked the plentiful supplies and superior organisation of their Nationalist opponents . Records show that about one tenth of the volunteers eventually found themselves imprisoned at least for a certain duration for crimes like desertion , breaking discipline , or for political reasons as the Stalinist tendency in the Brigades increased ( usually being accused of Trotskyism ) . Infighting between anarchists and communists , eventually resulting in outright battles with several hundred dead and the purging of rival communist groups like the Workers ' Party of Marxist Unification ( POUM ) , also further poisoned the atmosphere as Francisco Franco ' s victory came closer .