Career
From 1914 to 1918 he served as a soldier in the First World War part. After the end of the war, in 1919 he joined the Independent Social Democratic Party of Germany. In 1920 he moved to Munich, where in 1921 he joined the Communist Party of Germany.
In 1922 he became president of the Shoe Workers" Union.
From 1923 Buchmann was head of the KPD in Munich. In October 1923 he was imprisoned.
From 1932 he held the same position in the district of Württemberg. From 1924 to 1932 he belonged to the constituency Upper Bavaria-Swabia.
In May 1933, Buchmann was arrested and accused of high treason and in 1936 he was sent to Dachau concentration camp and Ludwigsburg prison.
In 1940 he was moved to Sachsenhausen concentration camp, 1942 he was moved to Flossenbürg concentration camp until his release in 1945. He was released at the end of the war and from 1945 he was chairman of the KPD for Northern Wuerttemberg. In 1952 he emigrated to the German Democratic Republic.
He died in 1975 in Berlin.