The Finnish Civil War of January to May 1918 ended with the defeat of the Red Guards, and roughly 80,000 prisoners were taken into camps while special treason courts processed their cases. Food was scarce in Finland that spring, rations in the camps were inadequate, and malnutrition combined with a summer epidemic to produce very high mortality: about 11,600 prisoners died in the camps, most of them between May and September 1918. The special courts issued 555 death sentences of which 113 were carried out, on top of several thousand summary executions during and immediately after the fighting, including roughly 290 in Tampere and 247 in Vyborg. Total deaths from the war and its aftermath came to about 36,000 in a country of some three million. Most prisoners were released under amnesties during 1918-19, but the camps and the terror left a division in Finnish society that lasted for decades; a state-funded national project later compiled a database of all those who died in the conflicts of 1914-22.
The victorious Finnish White government interned captured Red Guards, their families and suspected supporters in prison camps and tried them before special treason courts
Finnish official statistics put the population at about 3.13 million in 1918. The camps held some 80,000 people, close to the entire Red Guard establishment of roughly 75,000-100,000 combatants and supporters; about 12,500 died in the camps of hunger and disease within a year, the highest camp mortality in interwar Europe relative to population.
About 11,600 prisoners died in the camps, chiefly of malnutrition and of the disease that swept them in the summer of 1918; adding the 113 executions ordered by the treason courts and deaths shortly after release brings the camp-related toll to roughly 12,500-13,500. These figures come from Finnish state records compiled in the national war-victims project, and are relatively well established. Around 36,000 people died in the war and its aftermath in total.
Mass internment, camp starvation and the summary executions of 1918 are documented in Finnish state prison-camp and treason-court records and in the national compilation of war victims.
Finland