Viktor Yushchenko served as Ukraine’s third president from 2005 to 2010. In 2004, during a bitter and divisive campaign that left Yushchenko disfigured and ill due to a mysterious dioxin poisoning, his rival,Russian-backed Viktor Yanukovych, won in a runoff election. Amid widespread citizen protests over corruption and voter intimidation during the runoff, a movement emerged that became known as the Orange Revolution. The increased pressure from citizens led the Ukrainian Supreme Court to investigate and overturn the election results, leaving Yushchenko the victor. Since leaving office in 2010, Yushchenko has remained a vocal supporter of democracy in Ukraine, particularly in his outspoken condemnation of Russian aggression.