Questions tagged [20th-century]

For questions spanning a significant proportion of the 20th century. Questions focused on the latter decades should consider using the contemporary-history tag. Individual tags exist for specific decades.

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19
votes
6answers
60k views

Why was Germany held accountable for WW1?

The Treaty of Versailles forced Germany to accept all responsibility for the war. If the war was initially due to the assassination of Archduke Ferdinand by Serbian assassins, why did the Treaty of ...
20
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3answers
5k views

How were diplomats and their staffs treated when World War II was declared?

This could be a large and varied subject so I will restrict it to the 20th century and give two instances. In Sept 39, after Poland was invaded, the British diplomat in Berlin handed a note to the ...
15
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3answers
2k views

When passports/border checks became widespread?

I was reading the Wikipedia on passports, and there were numerous important dates in passport history, but I didn't find any date when passports became widely used documents for travelling. I see ...
188
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34answers
171k views

Why did Hitler attack the Soviet Union when he was still busy fighting the United Kingdom?

During World War 2, Hitler was fighting a war with Great Britain, but while fighting that war, he attacked the Soviet Union. Everyone knows that having to fight on two opposite fronts at once is bad......
41
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7answers
4k views

When did the practice of formally “declaring war” cease and why?

Here's a detailed description of ambassador Neville Henderson being received by the foreign ministry in Berlin in 1939. Perhaps the most famous example. He came in looking very serious, shook hands,...
92
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13answers
47k views

Why didn't Imperial Japan attack the Soviet Union during World War 2?

Japan and the Soviet Union shared a common border in Manchuria and the German invasion of the Soviet Union weakened the Soviets greatly. In view of the advantages to Japan in seeing the Soviet Union ...
29
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3answers
92k views

How many people in the US starved to death during the Great Depression?

I was trying to look this up earlier and could not easily find reliable information on the internet, mostly due to a new popular claim that 7 million people starved to death in the Great Depression! ...
20
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1answer
702 views

In which document was the exact course of the northern part of the German-Polish border decided?

While researching the answer to "How was Germany's border decided?", I didn't manage to find any documents which would precisely describe the borders between Germany and Poland between the points 53° ...
7
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5answers
2k views

What were the causes of the “Dardanelles” fiasco in World War I

During World War II, the Allies sent supplies to the Soviet Union via Murmansk/Archangelsk in the north, via Persia and the Caspian Sea in the south, and via the Tran-Siberian railroad. Why didn't ...
65
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9answers
15k views

Why did the USSR give Crimea to Ukraine?

In 1954 Soviets transferred Crimea from Russian Soviet Republic to Ukrainian Soviet Republic. Why is this strange? The whole act, at least officially, was meant to be "a gift", a token of friendship....
52
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13answers
26k views

Why did Hitler declare war on the USA?

Since there had not been any offensives launched by either side against the other, why declare war just because Japan had attacked the USA?
71
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12answers
26k views

Why, in the US, is Japanese brutality ignored compared with the Nazi brutality in WW2?

Instead of accepting too much of what I have read in my textbooks, I have read up a bit about WW2 on my own and have always pondered, why in the USA is the brutality and actions of the Japanese during ...
55
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10answers
32k views

Why did Britain and France not declare war against the Soviet Union when it invaded Poland in WW2?

At the beginning of WW2, although they were slow in actually attacking Germany, Britain and France did declare war against it after Germany invaded Poland. The reason for this was the treaty where ...
40
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10answers
5k views

What were Hitler's religious beliefs?

Hitler is often cited as an example of an evil atheist (along with Stalin and Mao). But there are several quotes from him that seem to indicate he believed in the Christian God - and even used this to ...
34
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6answers
138k views

Why did Italy abandon its alliance with Germany in WW1 and join the Allied side?

Before WW1 Italy was part of an alliance with Germany and Austria-Hungary, yet it didn't join them when the war started and it even joined the Allied side later during the war. Why did Italy do this? ...
14
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6answers
8k views

Why did the Germans fall behind the Americans in the development of the atomic bomb after an initial lead?

I actually know certain facts about this matter, but am seeking guidance in interpreting these facts into "theories." 1) Theory 1, Economic: The Americans spent something like $2 billion (in money of ...
11
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5answers
1k views

How many people were affected by the Holodomor [Famine-Genocide in Ukraine]

How many people were affected during the famine? Are there any sources for Soviet records on the Holodomor?
24
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5answers
4k views

How true is the statement “Soviet troops got into Berlin riding American trucks, walking in American boots and using American trains”?

In other words, how significant was American lend-lease in helping the Soviet front? Would the Soviets be suffering a lot more had lend-lease not happen, or was it not as significant as people make ...
11
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3answers
25k views

GDP per capita of major combatants before and after WWII?

Perhaps this is difficult to measure and maybe not even a good metric for anything meaningful, but what was the GDP and GDP per capita for nations around the world immediately before World War II? ...
5
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1answer
166 views

What family or other connection bound Chiang Kaishek and Cai Yuanpei, two ideological opposites?

Politically, Nationalist China's Chiang Kaishek must be considered a "strange bedfellow with Cai Yuanpei. Chiang was a disciplined, narrow-minded conservative of the type one might expect from a ...
13
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1answer
708 views

When did retailers stop wrapping purchases in paper and twine?

Listening to stories from relatives, it sounds like it was a near-universal practice (in the US, before the 1970s) to wrap retail purchases with brown paper and twine. Searching for information about ...
9
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2answers
1k views

Why did Japan take so long to attack Wuhan?

On December 13, 1937 Japan captured Nanjing; from there they could have continued up the Yangtze to attack Wuhan, then the second most populous Chinese city and de facto wartime capital. But ground ...
4
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1answer
533 views

Why don't the Americas use ISO paper sizes?

In the mid-sixties, most countries standardized on ISO paper sizes (A-series, B-series, etc.). The Americas didn't. Why not? (Around the same time there was a failed push in the US to switch to ...
47
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9answers
33k views

Why did Hitler not invade Sweden?

I was looking over a map of where the Nazis invaded and they never attacked Sweden. I was wondering why since it seems like a much better strategic move than invading Russia. Why might they have ...
66
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13answers
29k views

Why didn't France and UK invade Germany September 3rd 1939?

On September 3rd 1939, when UK and France declared war on Germany, both ordinary Polish people and government officials became enthusiastic. There were spontaneous demonstrations of support for the ...
33
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6answers
7k views

Was World War I a war of liberals against authoritarians?

An essay by Robert Kagan in the Washington Post, March 14, 2019, argues for rethinking the big theme of 20th-century history as a struggle between liberalism and authoritarianism, and for an ...
56
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9answers
20k views

Why are so many metros underground? Isn't that more expensive than an elevated system?

Starting with the London Underground in 1863, why are so many metros/subways built underground (as opposed to en elevated metro)? This requires a lot of digging and excavation, which to me seems a lot ...
32
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7answers
6k views

Why didn't Moldova unite with Romania?

Towards the collapse of the USSR, nationalism rose in Moldova. Nationalists proclaimed the linguistic and ethnic identity between Moldovans and Romanians. It seems that they strove toward unification ...
25
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14answers
33k views

What was the ratio of German to Soviet losses on Eastern front during different stages of the war?

I've read somewhere that the ratio of Soviet to German casualties on the Eastern front was 1.4 for the whole war. But what about data for different stages of the war? (this ratio wasn't constant after ...
23
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4answers
17k views

Did Hitler really support Subhash Chandra Bose's cause and did he do anything to help Bose?

Bose had come to realize that Gandhi's doctrine of non-violence was not doing much in forcing the British to retreat. He went to Germany to seek Hitler's assistance in India's struggle for freedom. ...
16
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1answer
5k views

How was titanium transported from Soviet Union to Area 51 for Oxcart?

Oxcart was one of its kind, a sophisticated aircraft designed during the Cold-War era. Its body was made up of titanium. Titanium was only found in substantial quantities in the then Soviet Union. The ...
12
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2answers
1k views

Why did Chicago and other cities choose an L (elevated metro) when most others chose underground subways?

From my related question, I'm trying to understand the decision-making that went into metro/subway design. Why did Chicago choose an elevated metro system instead of an underground subway? Most other ...
44
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6answers
9k views

Has Britain's 1940 invasion of Iceland been downplayed by historians?

On the face of it Operation Fork (Britain's invasion of Iceland in 1940) wasn't so terribly different from Germany's territorial landgrabs in 1939 and 1940. Britain and her allies will have ...
22
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3answers
3k views

Why was the Western Front so static in World War I?

Once the German advance was halted, neither side could seriously advance for two years. This seems like an extraordinarily long time. Why didn't anyone succeed at going around the trenches or striking ...
17
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5answers
28k views

Did either of the World Wars involve South or Central America?

Were any South or Central American nations besides Brazil involved (not necessarily officially) in either of the World Wars? If any were, I'd appreciate information on their degree of involvement.
13
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2answers
1k views

To what extent did the CPC avoid fighting with the Japanese?

There's general agreement that the Japanese invasion of China benefited the CPC by interrupting the civil war, forcing the KMT to fight the Japanese instead of continuing the CPC purge, which they ...
32
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2answers
920 views

Who, if any, in JFK's inner circle argued against the plans for the Bay of Pigs invasion?

Political discussions leading up to the Bay of Pigs invasion are a notorious example of 'groupthink' and the failure of a committee in coming to a well-informed decision. Accounts of the decision-...
25
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2answers
11k views

Why is Thailand considered an Axis power in WWII?

I read a Wikipedia article about military history of Thailand and it left me a taste of anti-Thai bias. It is known that Thailand in 1940 (after the fall of Paris and establishment of Vichy ...
22
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3answers
4k views

World War 1 Indian propaganda posters

In World War 1, because war broke out between the triple entente and the central powers (and they happened to have a lot of foreign colonies), the allies made posters to recruit soldiers from all ...
19
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5answers
4k views

Did the Germans lose the U-Boat war in World war II because of a shortage of quality, rather than quantity?

In the "Battle of the Atlantic" the Germans lost almost 800 of their 1200 submarines (nearly two-thirds) sinking 3,500 Allied merchant ships and 175 warships. Some 30% these "kills," were accounted ...
14
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6answers
9k views

Why did the Soviet Union's economy grow fast in the 1950's-1960's?

Communist economic systems self-implode. Today it has been recognized that Communism is bad for economic progress. There is no dispute that Communism makes countries poor based on what has happened in ...
13
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3answers
1k views

What sources or documentation exists to indicate Stalin's level of popularity in Russia today?

To what extent is Stalin still loved and/or respected by Russians (and for extra points former USSR states)? While articles like these news.bbc.co.uk/2/hi/europe/7802485.stm news.bbc.co.uk/2/hi/...
10
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3answers
1k views

How did the US fall behind in airplane technology from 1909-1917?

In December 1902 a Wright brothers built glider flew 600 feet. A World Record December 17, 1903 The Wright built the first successful powered airplane and Wilbur Wright flew 852 feet (260 m) in 59 ...
8
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1answer
13k views

What was the age of majority in 1900 United States?

What was the age of majority in 1900, in the United States? For women and for men? I am not asking about the age of consent. The age of majority is the chronological moment when minors cease to ...
7
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2answers
655 views

Did Spain and the Republic of China (Kuomintang) have diplomatic relations between 1931 and 1939? Were they friendly or unfriendly?

The Republic of China and the Kingdom of Spain had relations before 1931 (link). Did they maintain these relations after the Second Spanish Republic was established? After 1945, the Spanish State ...
7
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1answer
2k views

What were acceptance criteria/process to the Vienna Fine Arts Academy in 1906-7?

One famous applicant rejected by the Vienna Fine Arts Academy was of course, Hitler. I got to thinking: so who was accepted instead? To make sense of this we would need to know how was the admission ...
21
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4answers
17k views

Why is the capital of Turkey Ankara rather than Istanbul?

Turkey's predecessor state, the Ottoman Empire, had its capital in Istanbul. Are there any reasons for the capital's move when it became Turkey?
20
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1answer
2k views

What were the key factors to the fall of domestic socialism in the USA?

During the late 1800s, and early 1900s the United States saw the rise of trade union membership, the coming and going of the populist party, and watched the progressive era come to institute reforms ...
20
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3answers
3k views

To what extent was prohibition supported by the American public?

I read an answer here that said the prohibition was imposed on cities against their will. A bit of research on Google seem to say that it was pushed through because people didn't realize even wine ...
19
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3answers
5k views

What caused the 1979 Iranian revolution to become Islamic?

How did an initially anti-Shah revolution become an Islamic revolution? Was it because of Khomenei's return to Iran such that he seized the Iranian revolution?