what was the main reason of this war?
With  the invasion of Poland by Germany and subsequent declarations of war on Germany by France and the United Kingdom
World War II
World War II is generally considered to have begun on 1 September 1939, with the invasion of Poland by Germany and subsequent declarations of war on Germany by France and the United Kingdom. From late 1939 to early 1941, in a series of campaigns and treaties, Germany conquered or controlled much of continental Europe, and formed the Axis alliance with Italy and Japan. Under the Molotov–Ribbentrop Pact of August 1939, Germany and the Soviet Union partitioned and
aims and objectives of uno and its organs The organization's objectives include maintaining international peace and security, protecting human rights, delivering humanitarian aid, promoting sustainable development, and upholding international law. where is it headquartered? New York City when was this organization established? The UN was established after World War II with the aim of preventing future wars, succeeding the ineffective League of Nations has the organization or any of the individuals received any award? A number of agencies and individuals associated with the UN have won the Nobel Peace Prize in recognition of their work. Two Secretaries-General, Dag Hammarskjöld, and Kofi Annan, were each awarded the prize (in 1961 and 2001, respectively), as were Ralph Bunche (1950), a UN negotiator, René Cassin (1968), a contributor to the Universal Declaration of Human Rights, and the US Secretary of State Cordell Hull (1945), what can you tell me about its funding? The UN is financed from assessed and voluntary contributions from member states. The General Assembly approves the regular budget and determines the assessment for each member. This is broadly based on the relative capacity of each country to pay, as measured by its gross national income (GNI), with adjustments for external debt and low per capita income. you mentioned a war after which this organization established, can you tell me the powers involved in that war? It involved the vast majority of the world's countries—including all the great powers—forming two opposing military alliances: the Allies and the Axis how long did the war last? 1939 to 1945.
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World War II [SEP] Introduction
Key setbacks in 1943—including a series of German defeats on the Eastern Front, the Allied invasions of Sicily and Italy, and Allied offensives in the Pacific—cost the Axis its initiative and forced it into strategic retreat on all fronts. In 1944, the Western Allies invaded German-occupied France, while the Soviet Union regained its territorial losses and turned towards Germany and its allies. During 1944 and 1945, Japan suffered reversals in mainland Asia, while the Allies crippled the Japanese Navy and captured key Western Pacific islands.