The arrival of Nazi German leader Adolf Hitler to Mannerheim's birthday party 80 years ago was a media event of its time in Finland. Hitler had a special place in his heart for Finns, ambassadors' reports reveal.

Germany became an important partner for Finland in 1918, when Germany sent soldiers to support the Whites led by Mannerheim in the civil war. In June 1941, Finland invaded the Soviet Union together with Germany.

Finland cooperated closely with Germany. Finnish relations with Nazi leaders were still close in the summer of 1942, when the massacres of civilians on the Eastern Front and the mass extermination of Jews were already known.

For a long time, the debate on Finland's role alongside Germany was ignored as a historical necessity. What alternatives did Finland have and has our past been sufficiently addressed? What lessons have been learned from the war?