20th century

(19th century - 20th century - 21st century - more centuries)

Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s

The 20th century lasted from 1901 to 2000 in the Gregorian calendar. Common usage sometimes regards it as lasting from 1900 to 1999, but this is considered incorrect due to the nonexistence of a "Year Zero" before AD 1. The 20th century is also sometimes known as the nineteen hundreds (1900s), referring to the latter usage. Decades are almost always considered as starting with the "0" year and named accordingly ("1960s", etc.), so the first decade of a century technically overlaps back into the preceding one.

However, a number of arguments have been used to justify the common usage. One was advanced by the scientist Stephen Jay Gould, that the first decade had only nine years. Another was that the astronomical year numbering system for years does have a year zero, the year normally known as 1 BC. In 2000 the International Organization for Standardization clarified ISO 8601 to use the astronomical year numbering system, so retrospectively endorsing all the people who had celebrated the new century a few months earlier.

The term is also used to describe various periods that overlap with the calendar definition most notably the Short twentieth century and the Modern period. It also had a place in popular culture shown by its use in names such as 20th Century Fox and the Twentieth Century Limited.

Overview

The twentieth century saw a remarkable shift in the way that vast numbers of people lived, as a result of technological, medical, social, ideological, and political innovations. Terms like ideology, world war, genocide, and nuclear war entered common usage, and became an influence on the lives of everyday people. War reached an unprecedented scale and level of sophistication, approximately 57 million people died as a result of the Second World War (1939-1945) alone. The trends of mechanization of goods and services and networks of global communication, which were begun in the 19th century, continued at an ever-increasing pace in the 20th. In spite of the terror and chaos, the 20th century saw many attempts at world peace. As the 35th President of the United States John F. Kennedy said:

What kind of peace do we seek? I am talking about a genuine peace, the kind of peace that makes life on earth worth living. Not merely peace in our time, but peace in all time. Our problems are man-made, therefore they can be solved by man. For in the final analysis, our most basic common link is that we all inhabit this small planet, we all breath the same air, we all cherish our children's future, and we are all mortal.

Virtually every aspect of life in virtually every human society changed in some fundamental way or another during the twentieth century.

For a more coherent overview of the historical events of the century, see The 20th century in review.

The 20th century has sometimes been called, both within and outside the United States, the American Century, though this is a controversial term.

Important developments, events and achievements

Science and technology

The assembly line and mass production of motor vehicles and other goods allowed manufacturers to produce more and cheaper products. This allowed the automobile to become the most important means of transportation.
The invention of heavier-than-air flying machines and the jet engine allowed for the world to become "smaller". Space flight increased knowledge of the rest of the universe and allowed for global real-time communications via geosynchronous satellites.
Mass media technologies such as film, radio, and television allow the communication of political messages and entertainment with unprecedented impact
Mass availability of the telephone and later, the computer, especially through the Internet, provides people with new opportunities for near-instantaneous communication
Applied electronics, notably in its miniaturized form as integrated circuits, made possible the above mentioned rise of mass media, telecommunications, ubiquitous computing, and all kinds of "intelligent" appliances; as well as many advances in natural sciences such as physics, by the use of exponentially growing calculation power (see supercomputer).
The development of Nitrogen fertilizer, pesticides and herbicides resulted in significantly higher agricultural yield.
Advances in fundamental physics through the theory of relativity and quantum mechanics led to the development of nuclear weapons, the nuclear reactor, and the laser. Fusion power was studied extensively but remained an experimental technology at the end of the century.
The Big Bang model of cosmology was developed.
Inventions such as the washing machine and air conditioning led to an increase in both the quantity and quality of leisure time for the middle class in Western societies.
Most influential inventions in the 20th century: Antibiotics, Internet
More...

Wars and politics

Rising nationalism and increasing national awareness were among the causes of World War I, the first of two wars to involve all the major world powers including Germany, France, Italy, Japan, the United States and the British Commonwealth. World War I led to the creation of many new countries, especially in Eastern Europe.
The economic and political aftermath of World War I led to the rise of Fascism and Nazism in Europe, and shortly to World War II. This war also involved Asia and the Pacific, in the form of Japanese aggression against China and the United States. While the First World War mainly cost lives among soldiers, civilians suffered greatly in the Second -- from the bombing of cities on both sides, and in the unprecedented German genocide of the Jews and others, known as the Holocaust. Aftermath symptoms caused the Korean War, involving different countries, which Korea apart.
An Anglo-American covert operation named Operation Ajax (1953) overthrew the freely elected democratic Government of Iran and Iranian Prime Minister Mohammed Mossadegh. Excuses for the deposing included his nationalization of the oil industry which was previously operated by the Anglo-Iranian Oil Company. This event forms one of the root causes of the Middle-Eastern dislike of American policies and many events which surface today.
During World War I, in Russia the Bolshevik putsch led to the Russian Revolution (of October/November 1917). After the Soviet Union's involvement in World War II, Communism became a major force in global politics, spreading all over the world: notably, to Eastern Europe, China, Indochina and Cuba. This led to the Cold War and proxy wars with the western world, led by the United States.
The "fall of Communism" in the late 1980s freed Eastern and Central Europe from Soviet supremacy. It also led to the dissolution of the Soviet Union and Yugoslavia into successor states, many rife with ethnic nationalism.
Through the League of Nations and, after World War II, the United Nations, international cooperation increased. Other efforts included the formation of the European Union, leading to a common currency in much of Western Europe, the euro around the turn of the millennium.
The end of colonialism led to the independence of many African and Asian countries. During the Cold War, many of these aligned with the USA, the USSR, or China for defense.
The creation of Israel, a Jewish state in a mostly Arab region of the world, fueled many conflicts in the region, which were also influenced by the vast oil fields in many of the Arab countries.
Democratic nations finally began to extend voting privileges to all adults.
The Second Congo War starts in 1998 between several different nations
The Vietnam conflict was a major aspect of the 1960s and 1970s, and was the result of American attempts to suppress the spread of communism in south east asia.

Culture and entertainment

Movies, music and the media had a major influence on fashion and trends in all aspects of life. As many movies and music originate from the United States, American culture spread rapidly over the world.
After gaining political rights in the United States and much of Europe in the first part of the century, and with the advent of new birth control techniques women became more independent throughout the century.
Modern art developed new styles such as expressionism, cubism, and surrealism.
The automobile provided vastly increased transportation capabilities for the average member of Western societies in the early to mid-century, spreading even further later on. City design throughout most of the West became focused on transport via car. The car became a leading symbol of modern society, with styles of car suited to and symbolic of particular lifestyles.
Sports became an important part of society, becoming an activity not only for the privileged. Watching sports, later also on television, became a popular activity.

Disease and medicine

Although the availability and quality of medicine continued to improve, epidemic diseases continued to spread, aided by modern transportation. An influenza pandemic, the Spanish Flu, killed 25 million between 1918 and 1919, while AIDS is yet uncured and treatments remain too expensive for wide use in developing countries.
Advances in medicine, such as the invention of antibiotics, decreased the number of people dying from diseases. Contraceptive drugs and organ transplantation were developed. The discovery of DNA molecules and the advent of molecular biology allowed for cloning and genetic engineering.

Natural resources and the environment

The widespread use of petroleum in industry -- both as a chemical precursor to plastics and as a fuel for the automobile and airplane -- led to the vital geopolitical importance of petroleum resources. The Middle East, home to many of the world's oil deposits, became a center of geopolitical and military tension throughout the latter half of the century.
A vast increase in fossil fuel consumption leads to depletion of natural resources, while air pollution possibly leads to global warming and the ozone hole. The problem is increased by world-wide deforestation, also causing a loss of biodiversity. The problem of a depletion of natural resources is decreased by advances in drilling technology which led to a net increase in the amount of fossil fuel that is readily obtainable at the end of the century, as compared with the amount considered obtainable at the beginning of the century.

Significant people

Business

Aerospace pioneers

Military leaders

Religious figures

[Pope Pius XII]]
Pope John XXIII
Pope John Paul II
Mother Teresa of Calcutta
The 13th Dalai Lama of Tibet, Thubten Gyatso
The 14th Dalai Lama of Tibet, Tenzin Gyatso
The Rev. Martin Luther King Jr.
The Rev. Billy Graham
Mahatma Gandhi
Aurobindo Ghosh
Ramana Maharshi
Ayatollah Khomeini
Ayatollah Khamenei

Artists

Music

Film

Writers and poets

Sports figures

Decades and years

1890s	1890	1891	1892	1893	1894	1895	1896	1897	1898	1899
1900s	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909
1910s	1910	1911	1912	1913	1914	1915	1916	1917	1918	1919
1920s	1920	1921	1922	1923	1924	1925	1926	1927	1928	1929
1930s	1930	1931	1932	1933	1934	1935	1936	1937	1938	1939
1940s	1940	1941	1942	1943	1944	1945	1946	1947	1948	1949
1950s	1950	1951	1952	1953	1954	1955	1956	1957	1958	1959
1960s	1960	1961	1962	1963	1964	1965	1966	1967	1968	1969
1970s	1970	1971	1972	1973	1974	1975	1976	1977	1978	1979
1980s	1980	1981	1982	1983	1984	1985	1986	1987	1988	1989
1990s	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999
2000s	2000	2001	2002	2003	2004	2005	2006	2007	2008	2009

Modernism
20th century - Modernity - Surrealism - Existentialism
Modernism (music): 20th century classical music - Atonality - Jazz
Modernist poetry: Modernist poetry in English
Symbolism (arts) - Impressionism - Expressionism - Cubism - Modern architecture - Modern dance
...Preceded by Romanticism	Followed by Post-modernism...