Twentieth Century

The 20th century is arbitrarily divided into periods of 20 years. These include the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, and late 20th century. Recent events of the early 21st century are included in the 20th century.

   

Early 20th Century (1901-1920)

The early 20th century includes events of the early 1900s, late 1900s, early 1910s, and late 1910s. This period is noted for the First World War.

Early mid 20th Century (1921- 1940)

The early mid 20th century includes events of the early 1920s, late 1920s, early 1930s, and late 1930s. This period is noted for the Great Depression and the beginnings of the Second World War.

Mid 20th Century (1941- 1960)

The mid 20th century includes events of the early 1940s, late 1940s, early 1950s, and late 1950s. This period is noted for the Second World War, the beginning of the Cold War, and a decolonization movement.

Late mid 20th Century (1961 - 1980)

The late mid 20th century includes events of the early 1960s, late 1960s, early 1970s, and late 1970s. This period is noted for the Cold war and significant changes in society.

Late 20th Century (1981 - 2000)

This includes events of the early 1980s, late 1980s, early 1990s, and late 1990s. This period is noted for the end of the Cold War and the rise of radical Islam.

Early 21st Century (2000 - present)

This includes events of the early 2000s, late 2000s, early 2010s, and current events of the late 2010s.

Other history

Other periods of history including prehistory, antiquity, classical and medieval history, other modern history including the 16th century, 17th century, 18th century, and 19th century; and the future can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Sociology

Sociology can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Peoples of the world can be connected. Western civilization began to retreat from its political dominance of the rest of the world, but maintained a strong cultural and economic lead. Asiatic peoples assumed considerable importance. African peoples became politically independent, but were economically backward. American Indian peoples were submerged in Western Civilization and fewer events are associated with them. Communities and social mechanics can also be connected.

Institutions

Institutions including religion, government, economics, education, and family can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Culture

Culture including behavioral culture, conceptual culture, and material culture can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Anthropology

Anthropology including particular groups, human geography, human ecology, physicl anthropology, demography, and social foundations can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; the late 20th century including the early 1970s, late 1980s, early 1990s, and late 1990s, and the early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Particular groups

Particular groups can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century; the late 20th century including the early 19890s, late 1980s, early 1990s, and late 1990s; and the early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Royal Society

Human geography

Human geography including European geography, Asian geography, African geography, North American geogaphy, South American geography, and Oceanic geography can be used to examine the early 20th century, early mid 20th century, mid 29th century, late mid 20th century, late 20th century including the early 1980s, late 1980s, early 1990s, and late 1990s, and early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

European geography

European geography including Balkan geography, Eastern European geography, Central European geogrpahy, Italian geography, Iberian geography, Northwest European geogrpahy, Island European geography, and Scandinavian geography can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Balkan geography can be connected. Eastern European geography can be connected. Central European geography can be connected. Italian geography can be connected. Iberian geography can be connected. Northwest European geography can be connected. Island European geography can be connected. Scandinavian geography can be connected.

Asian geography

Asian geography including Southwest Asian geography, South Asian geography, Central Asian geogrpahy, North Asian geogrpahy, East Asian geography, and Southeast Asian geography can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Southwest Asian geography can be connected. South Asian geography can be connected. Central Asian geography can be connected. North Asian geography can be connected. East Asian geography can be connected. Southeast Asian geography can be connected.

African geography

African geography including North African geography, West African geogrpahy, North Central African geogrpahy, South Central African geography, East African geography, and Southern African geography can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

North African geography can be connected. West African geography can be connected. North Central African geograpy can be connected. South Central African geography can be connected. East African geography can be connected. South African geography can be connected.

North American geography

North American geography including Northeastern American geography, Northwestern American geography, and Southwestern American geography can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Northeastern American geography can be connected. Northwestern American geography can be connected. Southwestern American geography can be connected.

South American geography

South American geography including Amazon geography, Andean geography, and Argentine geography can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Amazon geography can be connected. Andean geography can be connected. Argentine geography can be connected.

Oceanic geography

Oceanic geography including Australian geography, Pacific Island geography, Antarctic geography can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Australian geography can be connected. Pacific Island geography can be connected. Antarctic geography can be connected.

Human ecology

Human ecology including human effects on the environment, relations with other life, and environmental effects on people can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century including the early 1980s, late 1980s, early 1990s, and late 1990s; and the early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Human effects on the environment can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Relations with other life can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Environmental effects on people can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Physical anthropology

Physical anthropology including human origins, racial variation, and human dispersion can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century; the late 20th century including the early 1980s, late 1980s, early 1990s, and late 1990s; and the early 21st century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Human origins can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Racial variation can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Human dispersion can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Demography

Demography including population change, population size and structure, migration, morbidity and mortality, and birth and fertility can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Population change can be used to eamine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Population size and structure can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Migration can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Morbidity and mortality can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Birth and fertility can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Social foundations

Social foundations including social group behavior, social group types, social control, social interaction, and social presentation can be used to examine the early 21st century.

Social group behavior can be connected. Social group types can be connected. Social control can be connected. Social interaction can be connected. Social presentation can be connected.

Personal studies

Personal studies including biography, psychology, and the human body can be used to examine the late 20th century and early 21st century.

Biography

Biography can be used to examine the early 21st century.

Psychology

Psychology including social psychology, personality, mental disorders, develomental psycholotgy, behavior patterns, mind, and behavioral elements can be used to examine the early 21st century.

Social psychology can be connected. Personality can be connected. Mental disorders can be connected. Develomental psychology can be connected. Behavior patterns can be connected. Mind can be connected. Behavioral elements can be connected.

Human body

Form and appearance can be connected. Human disease can be connected. The human life cycle can be connected. Human body functions can be connected. Human body systems can be connected.

Science

Physical and natural science including biology, earth science, astronomy, chemistry, and physics can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Biology

Biology including biohistory, ecology, systematics, organism biology, cell biology,and molecular biology can be connected.

Biohistory including Precambrian, Paleozoic, Mesozoic, and Cenozoic life can be connected. Ecology including biogeography, ecosystems, evolution, system ecology, community ecology, population ecology, and behavioral ecology can be connected. Systematics including animals, fungi, plants, protists, and microbes can be connected. Organism biology including behavior, life cycle, morphology and form, organ systems, tissues, and habitat can be connected. Cell biology including cell types, cell behavior, and cell structure can be connected. Molecular biology including nucleic acids, proteins, lipids, carbohydrates, other organics, and inorganics. can be connected.

Earth science

Earth science including geohistory, physical geography, atmospheric science, hydrospheric science, and geology can be connected.

Geohistory including Precambrian, Paleozoic, Mesozoic, and Cenozoic history can be connected. Physical geography including mapping, oceanic geography, and terrestrial geography can be connected. Atmospheric science including climatology, meteorology, and atmospheric structure can be connected. Hydrospheric science including oceanography, glaciology, groundwater, and fresh water hydrology can be connected. Geology including interior geology, geologic processes, landforms, petrology, and mineralogy can be connected.

Astronomy

Astronomy including galactic astronomy, stellar astronomy, and local astronomy can be connected.

Galactic astronomy including cosmology, galactic types, and galactography can be connected. Stellar astronomy including astrocartography, star groupings, stars, exoplanets, and the interstellar medium can be connected. Local astronomy including the sun, planetary systems, minor bodies, and the interplanetary medium can be connected.

Chemistry

Chemistry including chemical systems, chemical change, and chemical substances can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, and late 20th century.

Chemical systems including organic, inorganic, gas, liquid, and solid chemistry can be connected. Chemical change including nuclear rections, chemical reactions, and physical changes can be connected. Chemical substances including mixtures, compounds, and elements can be connected.

Physics

Physics including the structure of matter, quantum physics, relativity, electromagnetism, thermodynamics, and mechanics can be used to examine the early 20th century, early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

The structure of matter including exotic matter, common bulk matter, molecular physics, atomic physics, and subatomic physics can be connected. Quantum physics can be connected. Relativity including general relativity and special relativity can be connected. Electromagnetism including optics, magnetism, electric current, and electrostatics can be connected.

Thermodynamics including statistical mechanics can be connected. Nonclassical thermodynamics can be connected. Classical thermodynamics including thermodynamic laws, processes, and systems and states can be connected.

Mechanics

Mechanics including gravitation and celestial mechanics, general mechanics, rigid body mechanics, and particle mechanics can be connected.

Gravitation and celestial mechanics including nonrigid celestial mechanics, rigid body celestial mechanics, particle celestial mechanics, and Surface gravitation can be connected. General mechanics including wave mechanics, fluid mechanics, and deformable solid body mechanics can be connected. Rigid body mechanics including dynamic systems, static systems, rotational dynamics, and rigid body description and motion can be connected. Particle mechanics including particle systems, energetics, kinetics, kinematics, and particle description can be connected.


Created 25 Feb 2013 Last updated 23 Sep 2017