The first transport of 728 Polish political prisoners arrived in Auschwitz from the prison in Tarnów (150 km from the camp) on June 14, 1940. This date is accepted as the beginning of the operation of the camp. Shortly afterwards, next transports of political prisoners from the nearby prisons arrived in Auschwitz. Among them there were young men arrested while illegally crossing the Slovakian and Hungarian border in order to get to the Polish Army units forming in France, members of clandestine organizations, and people arrested in operations targeting the Polish intelligentsia. There were also several dozen Jews in the first transports.

(Mini dictionary of terms from the history of Auschwitz)