Walasiewicz started her athletic career at South High School, a school located in the historic Slavic Village neighborhood on the east side of Cleveland, Ohio. In 1927, she qualified for a place on the American Olympic team started by the Cleveland Press newspaper. However, Walasiewicz was not an American citizen and could not obtain citizenship under the age of 21, so she could not compete. The success of Halina Konopacka, a Polish athlete who won gold in the discus throw at the 1928 Summer Olympics, inspired Walasiewicz to join the local branch of Sokół, a Polish sports and patriotic organization active among the Polish diaspora. During the Pan-Slavic meeting of the Sokół movement in Poznań, she scored her first major international victories; she won five gold medals in the 60 metre, 100 metre, 200 metre and 400 metre races, as well as the long jump. She was asked to stay in Poland and join the Polish national athletic team, and she continued to run in American challenges and games.