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 including the early 1900s, late 1900s, early 1910s, and late 1910s; the early mid 20th century including the early 1920s, late 1920s, early 1930s, and late 1930s; the mid 20th century including the early 1940s, late 1940s, early 1950s, and late 1950s; the late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; the 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.

Anthropology

Anthropology including particular groups, human geography, human ecology, physical anthropology, demography, and social foundations can be used to examine the early 20th century including the early 1900s, late 1900s, early 1910s, and late 1910s; the early mid 20th century including the early 1920s, late 1920s, early 1930s, and late 1930s; the mid 20th century including the early 1940s, late 1940s, early 1950s, and late 1950s; the 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.

Personal studies

Personal studies including biography, psychology, and the human body can be used to examine th early 20th century including the early 1900s, late 1900s, early 1910s, and late 1910s; the early mid 20th century including the early 1920s, late 1920s, early 1930s, and late 1930s; the mid 20th century including the early1940s, late 1940s, early 1950s, and late 1950s; the late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; 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.

Biography

Biography can be used to examine the early 20th centtury, 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.

Psychology

Psychology including social psychology, personality, mental disorders, develomental psycholotgy, behavior patterns, mind, and behavioral elements can be used to examine the early 20th century, early mid 20th century, mid 20th century, the late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; 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.

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

Human body

The human body including form and appearance, human disease, the human life cycle, human body functions, and human body systems can be used to examine the early 20th century, early mid 20th century; the mid 20th century including the early 1940s, late 1940s, early 1950s, and late 1950s, the late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; the late 20th century including the eearly 1980s, late 1980s, early 1990s, and late 1990s, and the early 2000s including the early 2000s, late 2000s, early 2010s, and late 2010s.

Form and appearance 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. Human disease 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 human life cycle 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 body functions 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 body systems can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Science

Physical and natural science including biology, earth science, astronomy, chemistry, and physics can be used to examine the early 20th century including the early 1900s, late 1900s, early 1910s; and late 1910s; the early mid 20th century including the early 1920s, late 1920s, early 1930s, and late 1930s; the mid 20th century including the early 1940s, late 1940s, early 1950s, and late 1950s; the late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; 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.

Biology

Biology including biohistory, ecology, systematics, organism biology, cell biology,and molecular biology can be used to examine the early 20th century, early mid 20th century, mid 20th century including the early 1940s, late 1940s, early 1950s, and late 1950s; the late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; 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.

Biohistory including Precambrian, Paleozoic, Mesozoic, and Cenozoic life 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. Ecology including biogeography, ecosystems, evolution, system ecology, community ecology, population ecology, and behavioral ecology can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Systematics including animals, fungi, plants, protists, and microbes can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Organism biology including behavior, life cycle, morphology and form, organ systems, tissues, and habitat can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Cell biology including cell types, cell behavior, and cell structure can be used to examine the mid 20th century, late mid 20th century, late 20th century, and early 21st century. Molecular biology including nucleic acids, proteins, lipids, carbohydrates, other organics, and inorganics can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Earth science

Earth science including geohistory, physical geography, atmospheric science, hydrospheric science, and geology can be used to examine the early 20th century, early mid 20th century, the mid 20th century including the early 1940s, late 1940s, early 1950s, and late 1950s; the late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; the late 20th century including the early 1980s, late 1980s, early 1990s, and late 1990s; and the late 20th century including the early 2000s, late 2000s, early 2010s, and late 2010s.

Geohistory including Precambrian, Paleozoic, Mesozoic, and Cenozoic history 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 geography including mapping, oceanic geography, and terrestrial 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. Atmospheric science including climatology, meteorology, and atmospheric 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. Hydrospheric science including oceanography, glaciology, groundwater, and fresh water hydrology can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century. Geology including interior geology, geologic processes, landforms, petrology, and mineralogy can be used to examine the early mid 20th century, mid 20th century, late mid 20th century, late 20th century, and early 21st century.

Astronomy

Astronomy including galactic astronomy, stellar astronomy, and local astronomy can be used to examine the early 20th century; the early mid 20th century including the early 1920s, late 1920s, early 1930s, and late 1930s, the mid 20th century including the early 1940s, late 1940s, early 1950s, and late 1950s; the late mid 20th century including the early 1960s, late 1960s, early 1970s, and late 1970s; 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.

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 9 Feb 2018