In November 1936 MacDonald travelled to Barcelona with Guy Aldred's partner, Jenny Patrick, to represent and show the support of the Scottish anarchist movement for the Republican faction in the Spanish Civil War. In January 1937 she began to transmit regular English-language reports on the war on Barcelona's widely heard Anarchist radio station run by the National Confederation of Labor. In the crackdown following the events of May 1937 she assisted the escape of anarchists wanted by the Communist secret police and smuggled into prison letters and food for fellow anarchists held by regional authorities. Through her activities in helping anarchists escape Spain, she became renowned in the British press as the "Scots Scarlet Pimpernel". Between July and November 1937, she was a national figure in the newspapers, with daily reports and inquiries as to her whereabouts and activities.
Death of Bob Smillie
On 12 June 1937, Bob Smillie, who was a member of the Independent Labour Party that had been fighting with the POUM forces for the Republicans, died while being held by the Valencia police. The police stated that his death had been caused by peritonitis, however, rumours flew around Valencia that he had been beaten to death. MacDonald began reporting the latter version of events on her radio broadcasts and in newspaper articles. This eventually led to her own arrest. MacDonald eventually escaped custody and left Spain altogether, making her way back to Glasgow by November of 1937. Along the way she travelled through Paris and Amsterdam, where she denounced the actions of the Communists in Spain. She continued to publicly discuss the case of Bob Smillie, but her version of events was disputed in the UK by David Murray, a member of the Independent Labour Party who had also been in Spain. Murray insisted that Smillie had died of peritonitis, and he was generally believed until George Orwell returned to London in 1938 and also began to denounce the actions of the Communists in Spain. Georges Kopp, who had been Smillie's commander in Spain, also returned and supported the view that Smillie had been murdered.
Later years and death
After her return from Spain, Ethel MacDonald worked closely with Guy Aldred, Jenny Patrick, John Taylor Caldwell and other Glasgow anarchists on a shoestring publishing enterprise, The Strickland Press, which published regular issues of the USM organ, The Word. They continued their activities through World War II and the 1950s peace movement, with MacDonald considered as the unofficial manager, bookkeeper and printer of The Strickland Press. She and Guy Aldred donated their papers to the Mitchell Library in Glasgow. The collection numbers approximately 500 items consisting of Spanish newspapers, bulletins, newssheets, flyers, posters, pamphlets and photographs issued under the auspices of the CNT and the Iberian Anarchist Federation during 1936-1938. Ethel MacDonald was diagnosed with multiple sclerosis in February 1958 and lost her ability to speak. Within three years she died in Glasgow's Knightswood Hospital at the age of 51.
