At the time of Rydz-Śmigły's command, the Sanation camp embraced the ideology of Roman Dmowski, Piłsudski's nemesis. Rydz-Śmigły did not allow General Władysław Sikorski, an enemy of the Sanation movement, to participate as a soldier in the country's defense against the Invasion of Poland in September 1939. During World War II in France and then in Britain, the Polish government-in-exile became dominated by anti-Sanation politicians. The perceived Sanation followers were in turn persecuted (in exile) under prime ministers Sikorski and Stanisław Mikołajczyk.