Politically, Marx's legacy is more complex. Throughout the 20th century, revolutions in dozens of countries labelled themselves "Marxist"most notably the Russian Revolution, which led to the founding of the Soviet Union. Major world leaders including Vladimir Lenin, Mao Zedong, Fidel Castro, Salvador Allende, Josip Broz Tito, Kwame Nkrumah, Jawaharlal Nehru, Nelson Mandela, Xi Jinping, Jean-Claude Juncker and Thomas Sankara have all cited Marx as an influence. Beyond where Marxist revolutions took place, Marx's ideas have informed political parties worldwide. In countries associated with some Marxist claims, some events have led political opponents to blame Marx for millions of deaths, but the fidelity of these varied revolutionaries, leaders and parties to Marx's work is highly contested and has been rejected, including by many Marxists. It is now common to distinguish between the legacy and influence of Marx specifically and the legacy and influence of those who have shaped his ideas for political purposes. Andrew Lipow describes Marx and his collaborator Friedrich Engels as "the founders of modern revolutionary democratic socialism."