thumb|Karl Leisner, German stamp (2015); inscription: Bless also, o Most High, my enemies.
Karl Leisner (28 February 1915 in Rees – 12 August 1945 in Planegg, Germany) was a German Catholic priest interned in the Dachau concentration camp. He died of tuberculosis shortly after being liberated by the Allied forces. He has been declared a martyr and was beatified by Pope John Paul II on 23 June 1996.
Life
Leisner was born on 28 February 1915, the oldest of five children. When he was six years old, the family moved to Kleve, a city on the lower Rhine, where his father worked as a civil servant. He attended school and completed his gymnasium studies in 1934. During his youth, he became an altar boy and, at the suggestion of the high school chaplain, formed a Catholic youth group, the Saint Werner Group. These youth groups combined prayer with outdoor activities, such as camping and cycling. Leisner turned out to be a natural leader and became a youth leader in the 1930s, during the era in which the Nazis were beginning to take control of all youth organizations. In order to avoid Nazi interference, Leisner would often take his group on camping trips to Holland or Belgium.
In 1934, when he was nineteen, Leisner entered the seminary in Munich, and was named Diocesan Youth Leader by Clemens August von Galen, Bishop of Münster. He spent six months in compulsory agricultural work during which, despite Nazi opposition, he organized Sunday Mass for his fellow workers. In 1937, his parents' house was raided by the Gestapo, who seized his diaries and papers. These meticulously preserved documents tell how the spiritual young man became a religious leader.
On 25 March 1939, Galen ordained Leisner a deacon. Leisner was initially imprisoned in the Sachsenhausen concentration camp, but was moved to the Dachau concentration camp on 14 December 1940, where he became prisoner No. 22,356. Since he was a deacon, Leisner was assigned to the priests' block.
On 17 December 1944, Gaudete Sunday, a fellow prisoner, French Bishop Gabriel Piguet, secretly ordained him a priest.