United Nations Days and Their Themes: Dates and Facts
United Nations observance days for exams: how the UN declares a day, the lead agency behind each, the dates from February to December, and why themes change every year.
By GK24 Editorial Team· Published · 4 min read

The United Nations keeps a calendar of observance days, and General Knowledge papers draw from it every year. The safe way to prepare it is to learn three things about each day: the date, the body that declared it, and the event or document it commemorates. The theme is the fourth element, and it is the one that changes, because a fresh theme is announced for most days every year.
How the United Nations declares a day
An observance day comes into being in one of two ways. The General Assembly may adopt a resolution naming the day, as it did for the International Day of Yoga and the International Day of Non-Violence. Or a specialised agency may begin the observance within its own field — the World Health Organization for health days, UNESCO for education and culture, the International Labour Organization for work, the Food and Agriculture Organization for food and the UN Environment Programme for the environment. Whichever body declares the day also leads it, publishes the yearly theme and runs the campaign, so the agency and the day should be learnt as a pair.
United Nations Day and the Charter
United Nations Day falls on 24 October, the date on which the UN Charter came into force in 1945 after ratification by the majority of its signatories; the General Assembly asked member states to observe it from 1948. The organisation was founded at the San Francisco Conference with 51 original members, its headquarters are at New York, and it works in six official languages: Arabic, Chinese, English, French, Russian and Spanish. The week beginning 24 October is observed as Disarmament Week.
The calendar of United Nations days
| Date | Day | Declared or led by |
|---|---|---|
| 21 February | International Mother Language Day | UNESCO, 1999 |
| 8 March | International Women’s Day | UN from 1975; Assembly resolution 1977 |
| 21 March | International Day of Forests | General Assembly, 2012 |
| 22 March | World Water Day | Proposed at Rio, 1992; observed from 1993 |
| 7 April | World Health Day | WHO; marks its constitution of 1948 |
| 31 May | World No Tobacco Day | WHO, from 1988 |
| 5 June | World Environment Day | Assembly after Stockholm, 1972; led by UNEP |
| 12 June | World Day Against Child Labour | International Labour Organization, 2002 |
| 20 June | World Refugee Day | General Assembly, 2000 |
| 21 June | International Day of Yoga | General Assembly, 2014, on India’s proposal |
| 11 July | World Population Day | UNDP Governing Council, 1989 |
| 8 September | International Literacy Day | UNESCO, 1966 |
| 16 September | Day for the Preservation of the Ozone Layer | Marks the Montreal Protocol of 1987 |
| 21 September | International Day of Peace | From 1981; fixed to this date in 2002 |
| 2 October | International Day of Non-Violence | General Assembly, 2007; Gandhi’s birthday |
| 16 October | World Food Day | FAO; marks its founding in 1945 |
| 24 October | United Nations Day | Charter came into force, 1945 |
| 20 November | World Children’s Day | From 1954; marks the child rights texts |
| 1 December | World AIDS Day | WHO, from 1988 |
| 10 December | Human Rights Day | Marks the Universal Declaration, 1948 |
Themes: what changes and what does not
For most of these days the lead agency announces a theme for the year, and the campaign, the publications and the events follow it. A theme therefore belongs to one year alone, while the date and the declaring body stay fixed, which is why a candidate should never memorise a theme as though it were a permanent fact. When a paper does ask for one, it is almost always the theme of the year in which the examination is held, and it must be read from the agency’s own announcement. Past themes are asked as history: the second International Day of Yoga, in 2016, was observed with the theme Yoga for the achievement of the Sustainable Development Goals.
How to hold the calendar in memory
Group the days rather than listing them. The environment group falls between March and June — Forests on 21 March, Water on 22 March, Environment on 5 June. The health group belongs to WHO — 7 April, 31 May and 1 December. The rights group closes the year — Children on 20 November, Persons with Disabilities on 3 December, Human Rights on 10 December. India’s two contributions are easy to place: the International Day of Yoga on 21 June, which the General Assembly adopted in 2014 on India’s proposal with a record number of co-sponsors, and the International Day of Non-Violence on 2 October, the birth anniversary of Mahatma Gandhi.
Exam Point of View
Three kinds of questions come from this chapter. The first asks a date: which day falls on 21 June, 16 October or 24 October. The second asks what the date commemorates, and here the answer is a document or an event — the Charter for United Nations Day, the Universal Declaration for Human Rights Day, the WHO constitution for World Health Day, the Montreal Protocol for the ozone day. The third asks which agency leads the day, and the trap is to offer UNICEF where UNESCO is wanted, or the Assembly where the WHO began the observance. Questions on themes do appear, but a theme belongs to a single year, so answer from the year named in the question and never from memory of an old campaign.
Important Facts
| United Nations Day | 24 October; the Charter came into force in 1945 |
|---|---|
| International Day of Yoga | 21 June; Assembly resolution of 2014, first observed 2015 |
| International Day of Non-Violence | 2 October; Mahatma Gandhi’s birth anniversary; declared 2007 |
| World Environment Day | 5 June; led by UNEP, after the Stockholm Conference of 1972 |
| World Health Day | 7 April; WHO constitution of 1948; observed since 1950 |
| World Water Day | 22 March; proposed at the Rio Conference of 1992 |
| International Literacy Day | 8 September; declared by UNESCO in 1966 |
| World Population Day | 11 July; begun by the UNDP Governing Council in 1989 |
| Ozone Layer Day | 16 September; marks the Montreal Protocol of 1987 |
| World Food Day | 16 October; founding of the FAO in 1945 |
| Human Rights Day | 10 December; Universal Declaration of Human Rights, 1948 |
| World AIDS Day | 1 December; observed since 1988 |
| UN official languages | Arabic, Chinese, English, French, Russian, Spanish |
| Second Day of Yoga theme | Yoga for the achievement of the Sustainable Development Goals, 2016 |
Practice MCQs on this topic
What theme was decided to celebrate the second ‘International Day of Yoga’ in India?
- A.Yoga for the achievement of the Sustainable Development Goals
- B.Yoga for Peace
- C.Yoga for Wellness
- D.Yoga for Heart
Show answer
Correct answer: A. Yoga for the achievement of the Sustainable Development Goals
Explanation
The correct answer is A, Yoga for the achievement of the Sustainable Development Goals. The second International Day of Yoga fell in 2016, the year after the first observance of 2015, and the theme tied yoga to the Sustainable Development Goals that the United Nations had adopted in 2015, with the main event held at Chandigarh. Options B, C and D are themes of the kind announced in other years or simply invented for the question, and they are meant to attract a candidate who remembers only that the themes speak of peace, wellness or health. The lesson for the examination hall is to count the editions: the first day was in 2015, so the second was in 2016, and the theme must belong to that year. The day itself is observed on 21 June, following the General Assembly resolution of 2014 on India’s proposal.
United Nations Day is observed every year on:
- A.10 December
- B.24 October
- C.21 September
- D.16 October
Show answer
Correct answer: B. 24 October
Explanation
The correct answer is B, 24 October. On this date in 1945 the Charter of the United Nations came into force, after the required majority of signatory states had ratified it, and the General Assembly called upon members to observe the anniversary from 1948. The week beginning 24 October is marked as Disarmament Week. Option A, 10 December, is Human Rights Day, which commemorates the adoption of the Universal Declaration of Human Rights in 1948. Option C, 21 September, is the International Day of Peace, fixed to that date from 2002. Option D, 16 October, is World Food Day, which marks the founding of the Food and Agriculture Organization in 1945. All four are genuine United Nations days, so the question is answered by the event each date commemorates rather than by the date alone.
World Environment Day, led by the United Nations Environment Programme, is observed on:
- A.22 April
- B.22 March
- C.5 December
- D.5 June
Show answer
Correct answer: D. 5 June
Explanation
The correct answer is D, 5 June. The General Assembly established the day after the Stockholm Conference on the Human Environment of 1972, and it has been observed since 1974 under the lead of the UN Environment Programme, with a different country hosting the main event each year. Option A, 22 April, is International Mother Earth Day, declared in 2009. Option B, 22 March, is World Water Day, which grew out of the Rio Conference of 1992 and has been observed since 1993. Option C, 5 December, is World Soil Day, which the Assembly declared in 2013. The two June dates worth holding together are 5 June for the environment and 21 June for yoga, and the Stockholm Conference of 1972 is the event behind the first of them.
Human Rights Day, observed on 10 December, marks the adoption of which document?
- A.The Charter of the United Nations
- B.The Convention on the Rights of the Child
- C.The Universal Declaration of Human Rights
- D.The Montreal Protocol
Show answer
Correct answer: C. The Universal Declaration of Human Rights
Explanation
The correct answer is C, the Universal Declaration of Human Rights. The General Assembly adopted it on 10 December 1948 at Paris, and the observance of the anniversary began in 1950; the Declaration has thirty articles and is the most translated document in the world. Option A, the Charter of the United Nations, came into force on 24 October 1945 and is commemorated by United Nations Day. Option B, the Convention on the Rights of the Child, was adopted on 20 November 1989, which is why World Children’s Day falls on 20 November. Option D, the Montreal Protocol, was signed on 16 September 1987 and is marked by the International Day for the Preservation of the Ozone Layer. Each date therefore carries its own document, and that pairing is the whole question.
World Health Day is observed on 7 April because on that date in 1948:
- A.the constitution of the World Health Organization came into force
- B.the United Nations was founded
- C.the Universal Declaration of Human Rights was adopted
- D.the Stockholm Conference on the environment began
Show answer
Correct answer: A. the constitution of the World Health Organization came into force
Explanation
The correct answer is A, the constitution of the World Health Organization came into force. WHO became a specialised agency of the United Nations on 7 April 1948, and the first World Health Day was observed in 1950; the organisation announces a theme for the day each year and its headquarters are at Geneva. Option B is wrong because the United Nations came into being on 24 October 1945, when its Charter took effect. Option C is wrong because the Universal Declaration of Human Rights was adopted on 10 December 1948, an event marked by Human Rights Day. Option D is wrong on the year as well: the Stockholm Conference met in June 1972 and led to World Environment Day on 5 June. WHO also leads World No Tobacco Day on 31 May and World AIDS Day on 1 December.
The International Day of Non-Violence is observed on which date?
- A.30 January
- B.2 April
- C.15 August
- D.2 October
Show answer
Correct answer: D. 2 October
Explanation
The correct answer is D, 2 October. The General Assembly declared the day in 2007 and set it on the birth anniversary of Mahatma Gandhi, so that the date honours the leader whose method of non-violent resistance the resolution names. Option A, 30 January, is the day Gandhi was assassinated in 1948 and is observed in India as Martyrs’ Day, or Shaheed Diwas, but it is not the United Nations observance. Option B, 2 April, is World Autism Awareness Day, declared in 2007 as well, and it is placed here to catch a candidate who remembers only the year. Option C, 15 August, is India’s Independence Day and no United Nations day falls on it. Along with the yoga day of 21 June, this is the second observance in the UN calendar that comes directly from India.
International Literacy Day, observed on 8 September, was declared by which organisation?
- A.UNICEF
- B.UNESCO
- C.World Health Organization
- D.International Labour Organization
Show answer
Correct answer: B. UNESCO
Explanation
The correct answer is B, UNESCO. The United Nations Educational, Scientific and Cultural Organization proclaimed the day in 1966, and it was first observed in 1967; UNESCO also leads International Mother Language Day on 21 February and World Teachers’ Day on 5 October. Option A, UNICEF, works for children and leads campaigns around World Children’s Day on 20 November, and it is the distractor most often chosen because literacy is thought of as a matter for children. Option C, the World Health Organization, leads the health observances of 7 April, 31 May and 1 December. Option D, the International Labour Organization, declared the World Day Against Child Labour on 12 June. Learning the agency along with each day removes a whole family of questions in one stroke.
World Population Day is observed every year on:
- A.11 June
- B.11 May
- C.11 July
- D.11 August
Show answer
Correct answer: C. 11 July
Explanation
The correct answer is C, 11 July. The Governing Council of the United Nations Development Programme began the observance in 1989, taking the date from Five Billion Day, 11 July 1987, when the world’s population was estimated to have crossed five billion; the United Nations Population Fund now leads the campaign. Options A, B and D place the same day number in the wrong month and are offered for exactly that reason, because candidates remember the eleventh but not July. A second fact from the same chapter is often asked beside it: World Youth Day in the UN calendar is International Youth Day, observed on 12 August, declared by the General Assembly in 1999. Keep the July and August pair together to avoid the swap.
The International Day for the Preservation of the Ozone Layer, observed on 16 September, marks the signing of which treaty?
- A.Kyoto Protocol
- B.Paris Agreement
- C.Basel Convention
- D.Montreal Protocol
Show answer
Correct answer: D. Montreal Protocol
Explanation
The correct answer is D, the Montreal Protocol. The Montreal Protocol on Substances that Deplete the Ozone Layer was signed on 16 September 1987, and the General Assembly later fixed that date as the ozone day. Option A, the Kyoto Protocol, was adopted in 1997 under the climate convention and came into force in 2005, and it deals with greenhouse gases rather than ozone-depleting substances. Option B, the Paris Agreement, was adopted in 2015, also on climate change. Option C, the Basel Convention, of 1989, controls the movement of hazardous wastes across borders. The trap in this question is the general resemblance of environmental treaties, so tie each one to its subject: Montreal for the ozone layer, Kyoto and Paris for climate, Basel for hazardous waste and Ramsar for wetlands.
World Food Day, which marks the founding of the Food and Agriculture Organization, is observed on:
- A.16 October
- B.24 October
- C.1 December
- D.5 October
Show answer
Correct answer: A. 16 October
Explanation
The correct answer is A, 16 October. The Food and Agriculture Organization was founded on 16 October 1945 at Quebec in Canada, and the day has been observed in its memory since 1981; the FAO has its headquarters at Rome and leads the campaign every year. Option B, 24 October, is United Nations Day, the anniversary of the Charter coming into force in the same year, 1945, which is what makes the two dates easy to confuse. Option C, 1 December, is World AIDS Day, observed since 1988 under the World Health Organization. Option D, 5 October, is World Teachers’ Day, led by UNESCO since 1994. Notice that October carries three observances in this chapter — the second, the sixteenth and the twenty-fourth — and learn them as a set.
International Mother Language Day, declared by UNESCO, is observed on:
- A.21 March
- B.21 May
- C.21 February
- D.21 June
Show answer
Correct answer: C. 21 February
Explanation
The correct answer is C, 21 February. UNESCO proclaimed the day in 1999 and it has been observed since 2000, to promote linguistic diversity and mother-tongue education; the date recalls the language movement of 1952 in what is now Bangladesh. Option A, 21 March, is the International Day of Forests, declared by the General Assembly in 2012, and it is also the International Day for the Elimination of Racial Discrimination. Option B, 21 May, is the World Day for Cultural Diversity, again a UNESCO observance, which makes it a close distractor. Option D, 21 June, is the International Day of Yoga. Four days in this chapter fall on the twenty-first of a month, so the month, not the day number, is the fact to fix in memory.
Who announces the theme of a United Nations observance day for a particular year?
- A.The government of the host country
- B.The United Nations agency or office that leads that day
- C.The United Nations Security Council
- D.The International Court of Justice
Show answer
Correct answer: B. The United Nations agency or office that leads that day
Explanation
The correct answer is B, the United Nations agency or office that leads that day. The lead body — WHO for the health days, UNESCO for education and language, the FAO for food, UNEP for the environment, or a United Nations office where the General Assembly named no agency — publishes the theme, the campaign material and the programme for the year. Option A is wrong because the country hosting an event follows the theme rather than setting it, although for World Environment Day a host country is indeed announced. Option C is wrong because the Security Council deals with international peace and security, not observances. Option D is wrong because the International Court of Justice settles legal disputes between states. Since the theme changes each year while the date and the lead agency do not, a candidate should memorise the second pair and read the theme only for the current year.
Frequently Asked Questions
Why is United Nations Day observed on 24 October?
Because the UN Charter came into force on 24 October 1945, once the required majority of signatory states had ratified it. The General Assembly called on members to observe the date from 1948, and the week that begins on it is Disarmament Week.
Who proposed the International Day of Yoga and when was it adopted?
India proposed it, and the General Assembly adopted the resolution in December 2014 with a record number of co-sponsoring states. The day is observed on 21 June, the longest day in the northern hemisphere, and was first marked in 2015.
Do United Nations days have permanent themes?
No. For most days the lead agency announces a new theme every year to guide that year’s campaign. The date and the declaring body remain fixed, so a theme should be quoted only for the year it belongs to.
Which document does Human Rights Day commemorate?
The Universal Declaration of Human Rights, adopted by the General Assembly on 10 December 1948. The observance began in 1950, and the Declaration’s thirty articles remain the most translated document in the world.
Which United Nations days are connected with India?
Two in particular. The International Day of Yoga on 21 June came from an Indian proposal adopted in 2014, and the International Day of Non-Violence on 2 October, declared in 2007, marks the birth anniversary of Mahatma Gandhi.
Sources
- International Days and Weeks — United Nations
- The Charter of the United Nations and the history of the Organization — United Nations





