In 1939, during the Soviet invasion of Poland, the regime annexed Galicia forcing national-oriented activists to flee. Fearful of repressions by the Soviet regime Rudnytska moved to Nazi-occupied Kraków. Later, in 1940, she moved on to Berlin, where her son was finishing his studied, begun already in Lviv. In 1943, she arrived in Prague, where she published her book, "Zakhidna Ukraina pid bolshevykamy" (Western Ukraine under the Bolsheviks) in 1944. Continuing to write in exile, she moved to Berlin and then directed the Ukrainian Relief Committee in Geneva between 1945 and 1950. In 1950 moved to New York City, where she remained for eight years, before returning to Europe, first moving to Rome and finally settling in Munich. Some of her most known publications include: ""Ukraïns’ka diisnist’ i zavdannia zhinochoho rukhu" (The Ukrainian Reality and the Tasks of the Women's Movement, 1934), "Don Bosko: Liudyna, pedahoh, sviatyi" (Don Bosco: Man, Pedagogue, and Saint, 1963), and "Nevydymi styhmaty" (The Invisible Stigmata, 1971)".