Stalin was the most influential leader of the 20th century (meaning he effected the world the most).

Sounds like Pro wants to go with heads of state and a definition of influence that includes the use of force. So I'll set Gandhi aside, except to say that Gandhi's influence was profound for non-violent movements like the American Civil Rights movement and the Myanmar Republic's recent reforms in response to Aung San Suu Kyi's non-violent dissidence, as well as the many British colonies who achieved independence after India. I'll also set Freud aside except to say as the Father of Psychoanalysis, no other 20th century figure did more to popularize psychology. It is hard to imagine the ways our understanding of human personality and mental health would have evolved in the absence of Sigmund Freud's foundational thinking. Freud's work creates an essential context for massive bodies of human achievement in the 20th century- Art, Writing, Feminism and really all civil rights, Psychology, Sociology. This is not to say that Freud's work was itself so potent. Rather, the personality of the 20th Century is defined in so many ways by reaction and response to Freud. I expect Pro loses a bit of authority on the subject of the 20th Century simply by admitting he's never heard of Sigmund Freud.I'm content to contrast Winston Churchill's influence against that of Joseph Stalin. If I can establish that Churchill had a greater effect on the character and development of the 20th Century than did Stalin, than Pro's thesis that Stalin was the MOST influential will be disproved.Let's start out with a little experiment. Search Joseph Stalin on Google= 5,020,000 resultsSearch Franklin D. Roosevelt on google= 18,000,000 resultsSearch Adolph Hitler on google= 30,400,000 resultsSearch Winston Churchill on google= 53,900,000 resultsHardly conclusive, but instructive for the purposes of gauging relative interest in the digital age. In the 5 and 6 decades since their deaths, 10 times as many web pages are referencing Winston Churchill than Stalin. If this was simply demonstrating English language bias or American bias (I'm sure both are a factor), we'd expect to Roosevelt hits to be close to Churchill. The truth is that Churchill was so impactful that it is difficult to discuss many modern geopolitical issues without summoning his name. It would be impossible to describe all of Churchill's lasting accomplishments in the space of 8,000 characters, so I'll only touch on a few of the major achievements.*It should be noted that before entering politics in 1900, Churchill was already a celebrity, having fought as an officer in the Spanish, South African, and British armies in an astonishing number of engagements around the world: Afghanistan, Sudan, Transvaal, India and Cuba. His published books, newspaper and magazine articles describing these campaigns in vivid detail made him one of the most famous men in England.*As Colonial Undersecretary in 1906, Churchill was the principle force in granting equal vote and political rights to both Britons and Boers in the formation of the Union of South Africa, essentially forming the Whites in/Blacks and Indians out fault line around which all South African politics evolved in the 20th Century. If half the white had been disenfranchised in 1906, South African politics would have been very different over the past 100 years.*As President of the Board of Trade in 1909, Churchill authored the first universal minimum wage in history, set standards for Labor disputes and set up the National Labor Exchange, the British office of Unemployment.*As British Home Secretary authored the National Insurance Act, which provided nearly universal health care and unemployment benefits.*As First Lord of the Admiralty, Churchill was instrumental in converting British fleets from coal to oil just prior to WWI. He established the Royal Naval Air Service which later formed the basis for the world's first air force. Churchill is credited with defining the first practical application of tanks, developing, funding, and committing the first tanks used in warfare. (They are, in fact, called "tanks" because Churchill disguised the project as a vehicle for carrying water to the front lines). At the outset of WWI, Churchill ordered the seizure of two dreadnought battleships that Britain had built for the Ottoman Empire against the direct orders of his superiors. This incident became the deciding factor for the Ottoman Empire to ally with Germany and Austro-Hungary against the Triple Entente of Britain, France, and Russia. Without Churchill, the Ottoman Empire might never have entered the war, lost and then been carved up to form the modern Middle East. Churchill also ordered the disastrous invasion of Gallipoli which remains the most solemn and momentous event in the history of Austrailia and New Zealand.*Resigning after Gallipoli, Churchill commanded the 6th Royal Scots battalion on the front lines in Belgium, to the astonished appreciation of many Brits.*As Secretary of State for Air & War, Churchill oversaw the British intervention on behalf of the White Russian during the Russian Civil War, bombing Bolshevik ports and planes and supplying tanks.*As Colonial Secretary, Churchill created the most effective force fighting the Irish Republican Army, the Black & Tans. He was one of the negotiators and signatories of the Anglo-Irish Treaty from which modern Ireland was created. At the same time, Churchill was in charge of re-organizing the Middle East after the collapse of the Ottoman Empire. More than any other person, Churchill designed the shape of the modern Middle East. Churchill drew and enforced the borders of Palestine, Jordan, Saudi Arabia, Kuwait, Syria, and Iraq. Churchill decided whether Kurds were Iraqis or Kurdistanis. Churchill decided which Druze were Lebanese, or Palestinian, or Syrian. Churchill carved out Kuwait and placed it under British protection. Without Churchill, the Syrian Civil War might be very different or might not have taken place at all. Without Churchill, Saddam Hussein have had no reason to invade Kuwait sparking the Gulf and Iraq wars. Without Churchill support of Zionism, Jordan and Palestine would probably have been one state, making the creation of Israel impossible to imagine.*As First Lord of the Admiralty again in 1939, Churchill demanded the British offensive into Norway and began his famous National Broadcasts that prepared and bolstered the nation for war.*As Prime Minister and Minister of Defense mobilized English speaking peoples around the world for war against Germany and Japan. Here his influences are so many and so profound that hundreds of books are devoted to the subject. More than any other man, Churchill commuted Roosevelt and America to an anti-German position. More than any other man, Churchill preserved the Western flank against Germany until D-Day. After the war, Churchill and Stalin divided Europe, defined East and West Germany, modern Poland, Czechoslovakia and Yugoslavia. After the war, Churchill was the foremost opponent of Soviet Hegemony in Eastern Europe, giving speeches around the world that popularized the notions of Cold War, Iron Curtain, and a balance of force between superpowers.Churchill encouraged Muslim separatists in India and jailed Hindu separatists during the war while allowing Muslim separatists to campaign, prefiguring the partitioning of India and the emergence of Pakistan. Through it all, Churchill wrote every day, maintained a journal, and authored 38 books, winning the Nobel Prize for Literature for his history of the Second World War. After the war, Churchill participated in the dismantling of the British Empire. So, I'll refute that Churchill's influence was limited to 5 years in Great Britain. He was the leading light in British politics for nearly 50 years, and no other single person has drawn more international border lines or decided the fates of nationalities with a stroke of his pen.