24 October, United Nations Day: why this date, what happened in San Francisco in 1945, and how Hungary became a member

24 October is United Nations Day. According to the United Nations, the day marks the anniversary of the entry into force of the UN Charter in 1945. In 2026 it is the 81st anniversary. This article explains where the date comes from and how Hungary became a member.

Sources: UN – UN Day, UN – history, Permanent Mission of Hungary to the UN, New York (PDF, Hungarian), UN News, 2011.

AI illustration (artist's depiction).

In spring 1945, in the final weeks of the Second World War, representatives of 50 countries met in San Francisco. According to the UN's own history page, the United Nations Conference on International Organization ran from 25 April to 26 June. During those weeks the delegates drafted and signed the Charter, the organisation's founding treaty.

Signing did not yet bring the organisation into existence. The Charter had to enter into force, and that required ratification: the signatory states had to approve it through their own constitutional procedures as well.

According to the UN, the organisation officially came into existence on 24 October 1945, when the Charter had been ratified by China, France, the Soviet Union, the United Kingdom, the United States and a majority of the other signatories. These five countries are the permanent members of the Security Council. UN Day marks that anniversary.

Timeline compiled from the sources linked in this article.

Hungary was not among the founders. According to a historical overview published by Hungary's UN mission:

• the Paris peace treaty signed on 10 February 1947 already referred to future UN membership;
• Hungary submitted its application in April 1947;
• admission was delayed for years by the Cold War stand-off;
• in the end the General Assembly and the Security Council admitted 16 countries at once;
• Hungary became a member state on 14 December 1955, under the name Hungarian People's Republic.

The document links the 16-country package to West Germany's accession to NATO and the creation of the Warsaw Pact, both in the same year.

Admission needs two bodies. According to the Hungarian UN mission's overview, in 1955 the General Assembly and the Security Council together approved the admission of the 16 states. The Security Council's five permanent members are the same five countries whose ratification was needed in 1945 for the Charter to enter into force. An application could therefore depend on relations between the major powers: in Hungary's case, those relations kept the door closed for eight years.

The new membership was soon tested. The same document records that on 8 November 1956, after the revolution was crushed, Hungary's newly appointed UN representative read out the Kádár government's statement at the General Assembly. The "Hungarian question" stayed on the organisation's agenda for years afterwards.

Fifty countries took part in the 1945 conference. The most recently admitted member state is South Sudan: according to UN News, it became the 193rd member in 2011. The UN still has 193 member states today.

The round anniversary, the 80th, was marked in 2025; the UN's website links from its UN Day page to a separate section titled "The UN at 80". The organisation is now 81 years old, and in December 2026 Hungary will have been a member for 71 years.

1. Signing was not enough. The Charter entered into force only once the five major powers and a majority of signatories had ratified it.
2. The conference lasted two months. The text was worked out in San Francisco from 25 April to 26 June.
3. Hungarian membership began in a peace treaty. The 1947 Paris peace treaty already mentioned it.
4. Sixteen countries joined together. Hungary became a member in 1955 as part of a 16-state package.
5. The youngest member dates from 2011. South Sudan joined as the 193rd member.

• 24 October marks the 1945 entry into force of the UN Charter; 2026 is the 81st anniversary.
• 50 countries drafted the Charter in San Francisco.
• Hungary applied in 1947 and joined on 14 December 1955, together with 15 other states.
• Today there are 193 member states.

Related reading: 23 October 1956 – the history of the revolution · Blog archive.

Educational content. Data Analytic Investments is not affiliated with the United Nations or the institutions cited; names are used for identification only. Images labelled "AI illustration" are not photographs.