Janko Pleterski (1 February 1923 – 8 June 2018) was a Slovenian historian, politician and diplomat. He was born on 1 February 1923 in Maribor, Slovenia, then part of the Kingdom of Serbs, Croats and Slovenes. He attended high school in Ljubljana. In August 1941, he was arrested by the Fascist authorities of the Italian-occupied Province of Ljubljana and imprisoned in Alessandria, Italy. After the Italian armistice in September 1943, he returned to Ljubljana. In July 1944, he joined the partisan resistance. After the end of World War II, he worked at the Yugoslav foreign ministry in Belgrade as an expert on border issues with Italy and Austria. In 1953, he became a researcher at the in Ljubljana. In 1963, he obtained a PhD in modern history at the University of Ljubljana. Between 1970 and