K.L. Reich is a semi-autobiographical novel written by the Catalan author Joaquim Amat-Piniella. It is based on his experiences as a Spanish Republican prisoner in the Mauthausen concentration camp during the Second World War. The first version was written in Andorra between 1945 and 1946, following Amat-Piniella's liberation from the camp. However, its publication was delayed for 17 years by state censorship in Franco's Spain. It was finally published in 1963, first in Spanish translation and then in the original Catalan.