It's been twenty years, but now that the dust has settled somewhat, I think I can come up with an adequate list of the century's top innovators and outsized influencers.
Of course the trickiest inclusions are those towards the end of the decade. By 1999 Jeff Bezos wasn't yet a big deal, for example. Nor, more soberingly, was Osama bin Laden - even though both were active in the late 20th century. For this list, then, the impact had to be during the 20th century. Steve Jobs, for example, is on for the Macintosh - not for the iPhone of the 21st century.
And of course, although I hope this would be obvious, inclusion on the list doesn't mean you're a good person - Hitler was a key player of the 20th century, but we all recognize that sometimes the most important people are also the most vile.
Finally, the entrants are divided into five categories, and then arranged (roughly) chronologically by the dates of their main accomplishments.
100 Most Important People of the 20th
Century
Politicians
and Activists
Emmeline
Pankhurst (UK): Leader of the British women’s suffrage movement.
Vladimir
Lenin (Russia/USSR): Leader of the Russian Revolution and founder of the USSR.
Mohandas
Gandhi (India): Nonviolent advocate to end the British occupation of India.
Franklin
Delano Roosevelt (USA): President who ushered America through the Depression
and World War II.
Adolph
Hitler (Germany): Fascist dictator and force behind World War II and the
Holocaust.
Winston
Churchill (UK): Prime Minister during World War II and the early Cold War.
David Ben-Gurion
(Israel): Modern advocate of Zionism and founder and leader of Israel.
Mao
Zedong (China): Founder of the Chinese Communist Party and architect of the disastrous Great
Leap Forward and Cultural Revolution.
Jawaharlal
Nehru (India): India’s first post-independence leader who oversaw the Partition.
Faisal
of Saudi Arabia (Saudi Arabia): Monarch of Saudi Arabia as it modernized and developed
its oil.
Dag
Hammarskjold (Sweden): United Nations Secretary General largely responsible for the organization's early
successes.
Ho Chi
Minh (Vietnam): Communist leader of North Vietnam whose fight led to French
withdrawal.
Che
Guevara (Argentina, Cuba): Guerrilla revolutionary in Cuba, Angola, and others.
Martin
Luther King, Jr. (USA): Nonviolent pastor and American Civil Rights activist.
Ayatollah
Khomeini (Iran): Cleric leader of the Iranian Revolution.
Ronald
Reagan (USA): President who resuscitated conservative politics and economics in the west.
Lech
Walesa (Poland): Labor leader who opposed Soviet influence in Eastern Europe,
later President.
Liu
Xiaobo (China): Dissident and democratic activist involved in Tiananmen Square.
Michael
Gorbachev (USSR/Russia): Soviet leader whose reforms dismantled the USSR and helped end
the Cold War.
Nelson
Mandela (South Africa): Anti-Apartheid activist and first President of free
South Africa.
Scientists
and Inventors
Orville
and Wilbur Wright (USA): Inventors of heavier-than-air flight.
Albert
Einstein (Germany, USA, others): Physicist who developed the theory of relativity.
Leo
Baekeland (Belgium): Chemist who made breakthroughs in developing plastic.
Edwin
Hubble (USA): Astronomer who figured out there was a universe beyond the Milky
Way galaxy.
Werner
Heisenberg (Germany): Physicist who developed quantum mechanics.
Robert
Goddard (USA): Invented the first practical liquid-fuel rocket.
Philo
Farnsworth (USA): Invented the electrical television system.
Alexander
Fleming (UK): Developed antibiotics with the discovery of penicillin.
Enrico
Fermi (Italy, USA): Radiation physicist and developer of nuclear power.
Alan
Turing (UK): Inventor of the modern programmable computer and AI theorist.
Jacques
Cousteau (France): Marine explorer, educator, and conservationist, who helped develop
the underwater breathing apparatus.
William
Shockley (USA): One of the key inventors of the silicon microchip.
Jonas
Salk and Maurice Hilleman (USA): Vaccinologists who developed the main vaccines
of the century.
James
Watson and Francis Crick (UK&USA): Discovered the structure of DNA,
unlocking genetics research.
Louis
and Mary Leakey (UK): Paleontologists who helped discover humanity’s origins in
East Africa.
Jane Goodall
(UK): Primatologist who pioneered new methods in field work and conservation.
Norman
Borlaug (USA): Geneticist who increased global food security with the Green
Revolution.
Rachel
Carson (USA): Launched the environmental movement with improved understanding of
ecology and the dangers of human meddling in the ecosystem.
Neil
Armstrong, Buzz Aldrin, and Michael Collins (USA): First humans to travel to
the moon.
Tim
Berners-Lee (UK): Invented the World Wide Web.
Magnates
and Businesspeople
Willis
Carrier (USA): Developed and marketed modern electrical air conditioning.
Henry
Ford (USA): President of Ford Motors who developed the modern assembly line to make
mass-market cars.
Amadeo
Giannini (USA): Invented branch banking and began giving loans to regular
customers.
Coco
Chanel (France): Invented the boutique and helped launch the global fashion industry.
Walt
Disney (USA): Created the Disney Company with innovations in media and tourism.
David
Sarnoff (USA): Helped create broadcast television and oversaw many early
milestones.
Juan
Trippe (USA): Ushered in commercial air travel and the importance of jet aircraft.
Stephen
Bechtel (USA): President of the Bechtel Corporation, building megaprojects from
the Hoover Dam, to transit systems, to oil pipelines around the globe.
William
Levitt (USA): Real estate developer who produced the suburban housing of America
while spreading segregation.
Estee
Lauder (USA): Launched the modern, scientifically-sound, cosmetics business.
Leo
Burnett (USA): Created modern advertising by increasing the importance of visuals
and branding.
Ray
Kroc (USA): President of McDonalds who largely developed fast food culture.
Walter
Reuther (USA): Labor leader who oversaw the period of America’s strongest union
membership and used his clout to secure lots of liberal reforms.
Thomas
Watson Jr. (USA): Leader of IBM during its key mid-century developments.
Charles
Merrill (USA): President of Merrill-Lynch who got Americans to become
shareholders, and to invest in Wall Street.
Akio
Morita (Japan): Led Sony and oversaw the world of transistors and affordable
electronic goods.
Steve
Jobs (USA): Co-founder and President of Apple, launching the Macintosh.
Bill
Gates (USA): Co-founder and President of Microsoft, developing the Windows
operating system.
Sam Walton
(USA): President of Walmart, who developed the box store and helped kill the mom-and-pop
stores.
Rupert
Murdoch (Australia, USA): International media mogul in newspapers, books,
movies, and television.
Intellectuals
and Influencers
Sigmund
Freud (Austria, UK): Invented psychoanalysis and understanding of dreams, the
subconscious, and mental health.
Margaret
Mead (USA): Pioneering cultural anthropologist who fought predominating racist
theories of the time.
Lewis
Terman (USA): Developed the modern IQ test, and popularized the concepts of standardized
testing and personality tests in general.
Margaret
Sanger (USA): Activist, founder of Planned Parenthood, and educator who advocated
safe abortions and birth control, and helped develop the contraceptive pill.
Kurt Gödel
(Austria/Czechia, USA): Mathematician who developed the incompleteness theorems,
landmarks in mathematics and logic.
John
Maynard Keynes (UK): Economist who wove in vital safety nets into capitalist systems
to avoid and ease economic disasters.
Jean
Piaget (Switzerland): Created the field of child psychology, explaining the
different developmental stages of a child’s mind and behaviors.
John
von Neumann (Hungary, USA): Mathematical polymath who created game theory to
explain human behavior in everything from economics to how we interact in social settings.
Simone
de Beauvoir (France): Leader of the second-wave feminist movement for women’s civil rights.
Clark
Kerr (USA): University administrator who oversaw the creation of ‘multiversity’
tiered education as a way meeting the growing demand for higher education, which was then copied
around the globe.
Pope
John XXIII (Italy): Oversaw the formation of the Second Vatican Council which
introduced significant modern reforms into the Catholic Church.
Ludwig
Wittgenstein (Austria, UK): Philosopher whose revolutionary work on language
largely upended centuries of metaphysical philosophy.
Hannah
Arendt (Germany, USA): Political philosopher who tried to understand the role
of development of Nazism in Germany and “the banality of evil”.
Frantz
Fanon (France): Author and advocate of decolonization and post-colonial culture
and society.
Paulo Freire
(Brazil): Educator who showed how formal systems of education can be made to
not serve as systems of oppression, creating 'critical pedagogy'.
John
Rawls (USA): Political philosopher who made groundbreaking defenses of democratic
systems.
Wangari
Maathai (Kenya): Developed a successful NGO, the Green Belt Movement, that
focused on sustainable land manage on a country-wide scale.
Noam
Chomsky (USA): Pioneering linguist who helped bring down the then-widely influential theories
of behaviorist psychology.
The XIV
Dalai Lama (Tibet/China): Buddhist leader with global influence in peace movements
and advocate for religious freedom, especially in China.
Jared
Diamond (USA): Anthropologist and geographer who succinctly summarized why
certain parts of the world developed complex civilization while others did not.
Artists
and Icons
Helen
Keller and Anne Sullivan (USA): Inspirational icons for disability education
and rights.
Harry
Houdini (Hungary, USA): Escape artist and illusionist who exposed spiritualists
and psychics.
Pablo
Picasso (Spain): Painter who developed Cubism and helped launch modern art.
Igor
Stravinsky (Russia, France, USA): Modernist composer who redefined western classical
music.
James
Joyce (Ireland): Innovative novelist who created literary modernism.
Louis
Armstrong (USA): Jazz pioneer and innovator which led to the blues and other
musical forms.
Le
Corbusier (Switzerland, France): Modern architect who revolutionized building
design.
Charlie
Chaplin (UK, USA): Silent film star and comedian who helped create and popularize Hollywood.
Jesse
Owens (USA): Iconic Olympian who won four gold medals at the Berlin games in a
triumph for black representation in sport.
Anne
Frank (Netherlands): Teenage diarist who became an icon of the Holocaust.
Richard
Rodgers and Oscar Hammerstein II (USA): Developed and popularized western musical
theater.
The
Beatles [John Lennon, Paul McCartney, George Harrison, and Ringo Starr] (UK): Resuscitated
rock music and introduced a new maturity of lyrics and form.
Andrei
Sakharov (USSR): Dissident scientist who stood up to the Kremlin and the
nuclear arms race.
Jim
Henson (USA): Developed the idea of using children’s television as an
educational medium.
Amitabh
Bachchan (India): The king of Bollywood as it grew up from the Golden Era.
Pele
(Brazil): Internationally renowned Brazilian football (soccer) star and
record-holder.
Bruce
Lee (USA, Hong Kong): Globally popularized martial arts and the Wuxia film
genre.
Diana,
Princess of Wales (UK): Beloved "People's Princess" who helped redefine British royalty.
Harvey
Milk (USA): Iconic politician who represented and fought for gay rights.
Steven Spielberg
(USA): Film director who invented the modern blockbuster, action-adventure films.
So there you have it! If I goofed, do let me know.