AI-identified photos reveal Norman Bethune's blood refrigeration innovation in Spanish Civil War

A black-and-white photograph shows a man in a dark coat bent over some kind of work. Only when you flip the image upside down does the caption reveal itself: blood refrigeration for transfusions in river water. Another frame captures the same figure standing beside someone else in a place marked simply as Morata. The man's face is obscured, his identity a mystery—until you find him elsewhere in the archive, this time performing a transfusion on a wounded soldier during Spain's Civil War, his name finally legible in the caption.

These photographs have lived in the National Library's holdings for ninety years, but no one had assembled the pieces until recently. The man using the Tajuña River as an ice box to keep blood fresh was Norman Bethune, a celebrated Canadian physician who would pioneer the world's first mobile transfusion unit and, in doing so, transform how medicine responded to mass casualties on the battlefield. Pedro Corral, a Madrid regional deputy and longtime researcher of the Civil War's lesser-known chapters, made the identification using artificial intelligence to search through hundreds of digitized historical files. He jokes that bald men recognize each other—a profile view was enough to catch Bethune's likeness.

Bethune's presence at the Battle of Jarama in February 1937 has been documented for decades. What is new is photographic evidence of the blood work he performed in the region. Corral describes the discovery as rescuing an essential chapter of the war, one that speaks to human resilience in the face of horror. The techniques Bethune developed saved countless lives. Before his innovation, soldiers arriving at rear hospitals from the front lines had already bled out.

Corral found the photographs while searching for Morata, a place he has visited repeatedly to walk the war's landscapes. Alongside them in the archive sat images by Robert Capa, Walter Reuter, and others. Once he identified Bethune, he began the work of locating where the pictures were taken. He enlisted help from fellow deputies with ties to the area and the town's mayor, Gloria de la Torre. Juan Luis Moreno, a local Civil War expert who runs his own museum in the village, joined the search. They combed through nearly every mill along the Tajuña's floodplain before Moreno pinpointed the location: the Molino del Manto, a private estate now rented for weddings, technically within Chinchón's municipal boundaries. The black-and-white photograph shows two poplar trees beside the mill—one now reduced to stumps—and an irrigation channel carrying water from the Tajuña, where Bethune experimented with keeping blood in optimal condition in case the conflict damaged refrigeration equipment.

The mill's current owner, Iñigo Osset, recalls that when he purchased the property in the 1980s, an elderly woman told him a field hospital had operated there during the war. When they arrived, the place was in ruins. They found shell casings, bullets, surgical instruments scattered across the ground. Moreno describes Bethune as a brilliant hematologist and chest surgeon, a communist and adventurer who came close to death more than once. He had volunteered as a stretcher-bearer in the First World War before arriving in Madrid in November 1936, equipped with a Ford van he had purchased in London and loaded with medical supplies in Paris.

Before heading to the front, Bethune established his first blood bank in the Salamanca neighborhood, running radio and newspaper campaigns asking people to donate in exchange for meal vouchers and wine. He was already envisioning transfusions at the point of injury, not arm-to-arm transfers in hospitals. In December 1936, in Casa de Campo, he performed a transfusion on a gravely wounded young soldier and saved his life—the world's first mobile transfusion unit. Moreno emphasizes that others had done transfusions in hospitals before, but Bethune was the first to do it in the street. His work during the Battle of Jarama, the bloodiest engagement of the war's early phase with 20,500 casualties, proved essential. Yet his reputation became a liability. Spanish physicians, driven by envy, accused him of promiscuity, drunkenness, and disrespect for Spanish medical traditions, and they expelled him.

Unable to return to Spain, Bethune found new purpose in China's Manchurian conflict, where he became revered as a god-like figure. He saved so many lives that people touched him as he passed. He is now a national hero, the Western figure with more streets, plazas, and busts in China than any other foreigner. His medical texts were required reading in universities for years. There, operating without gloves, he cut himself with a scalpel. The infection killed him.