Theresienstadt. In the context of varying degrees of Communist orthodoxy in both countries during the period of Soviet domination of Eastern Europe through much of the late 20th century, historical research into the Holocaust was politicized to varying degrees. Marxist doctrines of class struggle were often overlaid onto generally received histories, which tended to exclude both acts of collaboration and antisemitism in these nations. The advance of the Einsatzgruppen, Aktion Reinhardt, and many other significant events in the Holocaust occurred in German-occupied Europe, outside the present-day borders of the Federal Republic. The history of the memorials and archives which have been erected at these sites in eastern Europe is associated with the Communist regimes that ruled these areas for more than four decades after World War II. The Nazis promoted an idea of an expansive German nation extending into territories where ethnic Germans had previously settled. They invaded and controlled much of Central and Eastern Europe, unleashing violence against various Slavic groups, as well as Jews, Communists, prisoners of war, etc. After the war, the eastern European nations expelled German settlers as well as long settled ethnic Germans (the Volksdeutsche) as a reaction to Nazi Germany's attempt to claim the eastern lands on behalf of ethnic Germans. Analogous processes elsewhere In some of its aspects, Vergangenheitsbewältigung can be compared to the attempts of other democratic countries to raise consciousness and come to terms with earlier periods of governmental and insurgency abuses, such as the South African Truth and Reconciliation Commission, which investigated human rights abuses by both the National Party Government in South Africa under apartheid and by senior members of the African National Congress including Winnie Mandela and by the ANC's paramilitary wing, Umkhonto we Sizwe. Comparisons have been made with the Soviet process of glasnost and perestroika, though this was less focused on the past than achieving a level of open criticism necessary for progressive reform to take place. It was widely assumed during this time that the Communist Party of the Soviet Union would maintain its monopoly on power. American journalist David Remnick, however, has argued that once Memorial was founded by former Soviet dissidents in 1987 and began independently researching and publicizing accurate historical information about Soviet war crimes and the location of mass graves containing the victims of the Red Terror, Stalinism, and the Gulag; the clock began ticking on the continued survival of the