The 20th Century was the bloodiest, costliest
century of warfare in human history. Two world wars, and a large
number of major revolutions, along with significant social,
political, and economic upheavals made the period from 1901 to
2000 of great importance in a historical and military
Below is a list (with links) of the major wars
of the twentieth century. Any such list is by nature somewhat
subjective, but the wars and conflicts listed below all had
signifcant importance in history. This list of 20th Century wars
is presented in rough chronological order, with the earliest
listed first, and descending toward the also war-filled 21st
The Second Boer War (1899-1902)--Britain
vs. The Boer Republics (Orange Free State and Transvaal) in what
is now South Africa.
Somali "Mad Mullah" Jihad
(1899-1905)--Somali tribesmen led by religious leader Muhammad
ibn Abd Allah Hasan waged a desert guerrilla war against Britain,
Italy and Ethiopia. Following repeated defeats by the Somalis, the
colonial powers offered him territory in Italian Somaliland in
exchange for peace. He resumed his war in 1908 and harassed the
occupiers of his country until 1920.
called the "Philippine Uprising", this was a war of independence
fought by the Filipinos against the occupying American military.
Filipino resistance was ruthlessly crushed.
The Boxer Rebellion (1899-1900)--
The Chinese secret
religious and nationalistic Society of the Righteous Harmonious
Fists (Boxers), initiated a rebellion against both foreign
colonizers, missionaries and their own government in 1899. By
1900, the Chinese government had co-opted the rebels and directed
their violent fury entirely upon the foreign presence in China.
The Boxers, aided by Chinese Imperial troops, besieged the
diplomatic legations (embassies) of the Western powers and Japan,
sparking a truly international response. A retaliatory relief
expedition composed of troops from: the United State, Great
Britain, France, Germany, Italy, Austria-Hungary, Russia and Japan
invaded China and captured the capital of Peking (now called
War(1911-1912)--(also known as
the Turco-Italian War and the Tripolitanian War)--Italy
decided to add to its growing African empire by attacking
Ottoman-ruled Tripolitinia (Libya). The Italian victory began the
very swift fall of the Ottoman Empire which would end with the
Empire's disintegration at the end of World War One in 1918. The
day after Ottoman Turkey made peace with Italy, the Balkan League
attacked in the First Balkan War (see below).
First Balkan War (1912-1913)--The Balkan
nations of Montenegro, Serbia, Bulgaria, and Greece defeated the
Ottoman Empire, and seized nearly all of the Ottoman Empire's
remaining European territories.
Second Balkan War (1913)--The victors in
the First Balkan War fell out among themselves, with Bulgaria
attacking Serbia and Greece in an attempt to gain more of the
spoils from the first war. Rumania, Montenegro, and the Ottomans
also joined the war against Bulgaria.
War One (1914-1918)--The
first "official" world war was originally known as "The Great
War," and also as "The World War."
The Turkish War of Independence
(1921-1922)--Greek invasion of Turkey. Is considered part
of Turkish War of Independence. The Greek offensive failed. See
also the Fall
of the Ottoman Empire page
war between Poland and Russia/The Soviet Union.
(1937-1945)-Part of World War Two
Italo-Ethiopian War (1935-1936)--(also known as the Abyssinian
War)--Italy's Fascist dicator, Benito Mussolini, wanted to conquer
a new "Roman Empire," and chose Ethiopia as his first victim.
Ethiopia had defeated Italy in the First Italo-Ethiopian War in
1896, and Mussolini sought revenge for that embarrassing Italian
defeat. This war exposed the inherent weaknesses of the League of
Nations (an earlier and very weak version of the United Nations)
when it was unable to prevent war. Italy successfuly conquered
Ethiopia in 1936. During World
British, Commonwealth, Free French, Free Belgian, and Ethiopian
forces liberated Ethiopia in 1941
Spanish Civil War
(1936-1939)--The Spanish Civil War began as a right-wing
rebellion against the leftist Republican government of Spain. Led
by General Francisco Franco, the Nationalist rebels fought a long
and bloody civil war against their Republican foes. Franco was
received significant military aid from Nazi Germany and Fascist
Italy. The Republican side was aided by the Soviet Union. Franco
won the war in 1939 and set up a Fascist government. This war is
considered one of the precursor conflicts leading to
(1945-1991)-Worldwide conflict between two alliances, one led
by the United States (generally referred to as The West) and the
other led by the Soviet Union (generally referred to as The East,
or as the Communist Bloc). China was for a time an ally of the
Soviets, but broke away in the 1960s, an pursued their own Cold
War policies against the West.
first major military conflict of the Cold War. Communist rebels
supported by Yugoslavia and other Communist nations fought against
the pro-Western Greek government, which was given significant
support by the United States and Great Britain. The war ended with
a government victory.
--The "First IndochinaWar" was really a regional conflict
involving France, as the colonial ruler of "French Indochina,"
against the nationalist (but Communist) rebels seeking
independence for Vietnam, Laos, and Cambodia. This war was a part
of the Cold War, since in also involved the United States (and to
a lesser extent), Great Britain, aiding their ally France, while
the Communist rebels (the Viet Minh, Pathet Lao, and Khmer
Issarak), enjoyed aid from the Soviet Union and Communist China.
Below are the "smaller" conflicts that in part made up the First
Indochina War. This war led directly to the Second Indochina War,
which in the United States is best known as the Vietnam
Indochina War (1946-1954) --(known in Vietnam as "The
French War")--Communist Viet Minh rebels led by Ho Chi Minh
waged a successful war of independence against French colonial
forces who re-occupied Indochina following the Japanese defeat
War Two. The
Viet Minh were aided by the Soviet Union and by Communist
China. France received significant material support from the
United States. France agreed to grant independence to North
Vietnam, South Vietnam, Laos, and Cambodia following the Viet
Minh victory over French troops at Dien Bien Phu.
Pathet Lao War
(1950-1954)--Laotian communist forces (The Pathet
Lao) were allied with the Viet Minh fought against French
colonial forces. Independence achieved after the Vietnamese
communists defeated the French at Dien Bien Phu. The Pathet Lao
later continued their war against the new Laotian government,
finally taking over the country in 1975.
Khmer Issarak War
(1950-1954)--Cambodian (Khmer) communist forces allied with
the Viet Minh fought against French colonial forces.
Independence achieved after the Vietnamese communists defeated
the French at Dien Bien Phu. The Khmer communists (Khmer Rouge)
later continued their war against the new Cambodian government,
finally taking over the country in 1975.
First Kashmir War
(1947-1948)--First war between India and Pakistan over
possession of Kashmir.
War (1948-1949)-When Israel announced independence in May,
1948, the armies of Egypt, Transjordan, Saudi Arabia, Iraq, Syria,
and Lebanon attacked Israel in support of the local Arabs in
Palestine/Israel. This began the long-running and current
(1948-1960)-Communist insurgency against the new Malayan
government. Britain, Australia, and other Commonwealth nations put
down the insurgency in what would be the only outright military
victory of the Western powers against the Communists in the Cold
Second Indochina War
(1956-1975) --The so-called "Vietnam War" was really a
regional and international conflict involving not just North and
South Vietnam and the U.S. but also embroiling Laos, Cambodia,
Thailand, South Korea, Australia and New Zealand. Below are some
of the "smaller" conflicts that in part made up the Second
Indochina conflict included:
(1956-1975)--The Communist North Vietnamese and the
southern Viet Cong engaged in a long war to overthrow the
pro-American government of South Vietnam. The U.S. and other
allied nations sent troops to aid the Saigon regime. The last
U.S. combat troops left in 1973 and Saigon fell to the North
Vietnamese on April 30, 1975. Known in the U.S. and much of the
world as "The Vietnam War." Known in Vietnam as "The American
Laotian Civil War
(1959-1975)--North Vietnam sent large numbers of troops
into Laos to aid the Communist Pathet Lao against the
U.S.-backed Royal Laotian government. The Pathet Lao seized
power in 1975 and maintains a good relationship with
War (1967-1975) --North Vietnam sent large numbers of
troops into Cambodia to aid the Communist Khmer Rouge against
the U.S.-backed Cambodian government. The North Vietnamese Army
(NVA) had maintained a large presence in eastern Cambodia for
years prior to the beginning of the Khmer Rouge war in 1967.
Following the fall of the U.S.-backed governments in Cambodia
and South Vietnam, the two former Communist allies engaged in
warfare between themselves. (See below).
Yemen Civil War
(1962-1970)-- Egypt sent troops to support the Yemeni
Republican government against Royalist rebels supported by Saudi
Arabia. This was a major rift in the Arab world.
but bloody border war between China and India.
Second Kashmir War
(1965)--Second war between India and Pakistan over
War(1967)-- Israel defeated
the combined forces of Egypt, Jordan, Syria, and Iraq in six days.
This is considered the 3rd major Arab-Israeli War. Israel captured
the Gaza Strip and Sinai Peninsula from Egypt, the West Bank and
East Jerusalem from Jordan, and the
Golan Heights from Syria.
Warsaw Pact Invasion of Czechoslovakia
(1968)--The armed forces of the Communist Warsaw Pact (Soviet
Union, East Germany, Poland, and Hungary) invaded Czechoslovakia
to bring down a reformist Czech government.
Bengali War of
Independence (1971)--Can also be
considered a Pakistani civil war. East Pakistan rebelled against
West Pakistan, seeking independence. India intervened and helped
East Pakistan break away and become the new nation of
Yom Kippur War/Ramadan War (1973)--Egypt
and Syria launched a surpise attack on Israeli forces in the
occupied Sinai and Golan
Heights. While the Arab nations
failed to re-capture these territories, this conflict eventually
led to the 1979 Egypt-Israel Peace Treaty.
Lebanese Civil War
(1977-1978)- Ethiopia against Somalia and Somali rebels in the
Ogaden desert area. The Soviet Union provided huge amounts of
material and logistcal support and Cuba sent thousands of troops
to fight on Ethiopia's side. This war was a part of the Cold
Third Indochina War
their war against the U.S.-sponsored regimes in Saigon and
Phnom Penh, the North Vietnamese and the Khmer Rouge were able
to mask their ideological differences and ignore the historical
hostility between their two peoples. After taking power though,
these differences turned violent. Beginning with low-level
cross-border raids and escalating into full-fledged war in late
December of 1978 when Vietnam launched a massive conventional
invasion of Cambodia, swiftly occupying the nation within days.
Vietnam set up a new government in Phnom Penh with Khmer Rouge
defectors but found itself immersed in a long and difficult war
of occupation as the Khmer Rouge returned to the guerrilla
warfare they knew so well. Vietnamese troops left after more
than a decade, with the friendly government of Heng Samrin in
control of most of Cambodia.
17-Mar. 16, 1979)-- Similar to the difficulties between
Cambodia and Vietnam, the Hanoi regime enjoyed good relations
with China during the war against the United States and South
Vietnam, but once that conflict ended, ideological and
historical differences interfered with Sino-Vietnamese
relations. Using the Vietnamese invasion of Cambodia as a
pretext, China launched a massive attack along their common
border. Vietnam's border troops put up a very good defense,
causing major casualties to the Chinese People's Liberation
Army (PLA). Within a month of the invasion, China basically
declared that it had taught Hanoi a lesson and withdrew.
Results of this war include: moving Hanoi closer to the Soviet
Union, which was a rival of China; a modernization of the PLA
as China realized they did not do very well against a smaller
country; and the beginning of a long-lasting but low-level
border conflict with between Vietnam and China. (See
Border Clashes (1979-1988)--After the Chinese invasion of
Vietnam in 1979, continued warfare and infiltration along the
border kept these two neighbors in a state of low-level
warfare. The two Communist neighbors now maintain cordial
relations, but further research is needed to ascertain when the
cross-border raids and artillery exchanges ended.
(1979-1981)--Though technically not a war, this was a major
crisis that nearly brought the U.S. and Iran to war, and the
repercussions of this conflict are still felt today. (see
for more information on the recent issues between America and
Soviet Invasion of
Falkland Islands War
Israeli Invasion and
Occupation of Southern Lebanon (1982-2000)