Kazickas' grandparents, due to their involvement in the Uprising of 1863, were deported to interior of Russia, where he was born in Chernaya Padina, Saratov Oblast. The family returned to Lithuania in 1922. Kazickas studied economics at Vytautas Magnus University (1937–1940) and Vilnius University (1941–1942). In Vilnius he worked at Vilnius municipality and was involved in resistance movements. In 1944, as Soviet Union was winning the war against Nazi Germany, he retreated to Germany, where he lived in displaced person camps and attended University of Tübingen. In 1947, he was admitted on a scholarship to post-graduate program at Yale University. In 1951, Kazickas defended his thesis about sovietization of Czechoslovakia and was awarded Ph.D. He turned down professorship at Georgetown University to establish Neris International, Inc. with fellow Lithuanian refugee Juozas Valiūnas. The Manhattan-based firm became a major exporter of coal to post-war Germany and Italy.