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Komorowski took office on August 6, 2010, succeeding Lech Kaczyński, who died in the Smolensk air crash. He had previously served as the Marshal of the Sejm, the lower house of the Polish parliament, from 2007 to 2010. Komorowski's presidency was marked by the economic recovery from the global financial crisis, as well as by the signing of the Lisbon Treaty and the country's subsequent entry into the Schengen Area.