October has part(s) October 31
Last Monday: October 31
October Holiday (Ireland)Fixed observances
October 1
Armed Forces Day (South Korea)
Children's Day (El Salvador, Guatemala, Sri Lanka)
Day of Prosecutors (Azerbaijan)
Continuance of German-American Heritage Months, which runs from September 15 – October 15   (United States)
Continuance of National Hispanic Heritage Month which runs from September 15 – October 15 (United States),
Ground Forces Day (Russia)
Independence Day (Cyprus)
Independence Day (Nigeria)
Independence Day (Palau)
Independence Day (Tuvalu)
International Coffee Day
International Day of Older Persons
International Music Day
Lincolnshire Day (United Kingdom)
National Day of the People's Republic of China (People's Republic of China)
Pancasila Sanctity Day (Indonesia)
Teacher's Day (Uzbekistan)
Unification Day (Cameroon)
World Vegetarian Day
October 2
Batik Day (Indonesia)
Feast of the Guardian Angels
National Grandparents Day (Italy)
Gandhi's birthday-related observances:
Gandhi Jayanti (India)
International Day of Non-Violence
World Day for Farmed Animals
Independence Day (Guinea)
October 3
Gaecheonjeol (South Korea)
German Unity Day (Germany)
National Day (Iraq)
Morazán Day (Honduras)
October 4
Feast of Saint Francis of Assisi
Cinnamon Roll Day (Sweden)
Day of Peace and Reconciliation (Mozambique)
Independence Day (Lesotho)
World Animal Day
The beginning of World Space Week (October 4–10)
October 5
Armed Forces Day (Indonesia)
Constitution Day (Vanuatu)
Engineer's Day (Bolivia)
International Day of No Prostitution
Republic Day (Portugal)
Teachers' Day (Pakistan)
Teachers' Day (Russia)
World Teachers' Day
October 6
Day of Commemoration and National Mourning (Turkmenistan)
Dukla Pass Victims Day (Slovakia)
German-American Day (United States)
Memorial Day for the Martyrs of Arad (Hungary)
National Noodle Day (United States)
Teachers' Day (Sri Lanka)
Yom Kippur War commemorations:
Armed Forces Day (Egypt)
Tishreen Liberation Day (Syria)
October 7
Our Lady of the Rosary
International Trigeminal Neuralgia Awareness Day
Teachers' Day (Laos)
October 8
Air Force Day (India)
Arbor Day (Namibia)
National Independence Day (Croatia)
Navy Day (Peru)
October 9
Hangul Day (South Korea)
Independence Day (Uganda)
Independence of Guayaquil (Ecuador)
Leif Erikson Day (United States, Iceland and Norway)
National Day of Commemorating the Holocaust (Romania)
Takayama Autumn Festival (Takayama, Japan)
World Post Day
Valencian Community Day (Spain)
October 10
Arbor Day (Poland)
Capital Liberation Day (Vietnam)
Double Ten Day (Taiwan)
Fiji Day (Fiji)
Finnish Literature Day (Finland)
Independence Day (Cuba)
Party Foundation Day (North Korea)
World Mental Health Day
October 11
General Pulaski Memorial Day (United States)
International Day of the Girl Child
International Newspaper Carrier Day
National Coming Out Day (multinational, including United States, United Kingdom and Switzerland among others)
Old Michaelmas Day (Celtic)
Revolution Day (Republic of Macedonia)
October 12
Children's Day (Brazil)
Discovery of America by Columbus-related observances (see also October 8):
Columbus Day (Honduras)
Día de la Hispanidad or Fiesta Nacional de España, also Armed Forces Day (Spain)
Día de la Raza (El Salvador, Uruguay)
Día de la Resistencia Indígena, "Day of Indigenous Resistance" (Venezuela)
Día de las Américas (Belize)
Día de las Culturas, "Day of the Cultures" (Costa Rica)
Día del Respeto a la Diversidad Cultural, "Day of respect for cultural diversity" (Argentina)
Discovery Day (The Bahamas, Colombia)
Feast for Life of Aleister Crowley, celebrated as "Crowleymas" (Thelema)
Fiesta Nacional de España (Spain)
Freethought Day
Independence Day (Equatorial Guinea), celebrates the independence of Equatorial Guinea from Spain in 1968.
UN Spanish Language Day (United Nations)
October 13
Azerbaijani Railway Day (Azerbaijan)
Doi taikomatsuri October 13–15 (Shikokuchūō, Ehime, Japan)
International Day for Natural Disaster Reduction
National Police Day (Thailand)
Paramedics' Day (Poland)
Rwagasore Day (Burundi)
October 14
World Standards Day
October 15
Breast Health Day (Europe)
Evacuation Day  (Tunisia)
Global Handwashing Day
King Father's Commemoration Day (Cambodia)
National Latino AIDS Awareness Day (United States)
Pregnancy and Infant Loss Remembrance Day (United States and Canada)
Spirit Day (International observance)
Teachers' Day (Brazil)
White Cane Safety Day (United States)
October 16
World Food Day
Pope John Paul II Day (Poland)
World Anaesthesia Day
October 17
Dessalines Day (Haiti)
International Day for the Eradication of Poverty
Loyalty Day (Argentina)
October 18
Alaska Day (Alaska, United States)
Independence Day (Azerbaijan)
Necktie Day (Croatia)
Persons Day (Canada)
World Menopause Day
October 19
Constitution Day (Niue)
Mother Teresa Day (Albania)
World Toilet Day
October 20
Arbor Day (Czech Republic)
Heroes' Day (Kenya)
Revolution Day (Guatemala)
Vietnamese Women's Day (Vietnam)
World Osteoporosis Day
World Statistics Day
October 21
Apple Day (United Kingdom)
Armed Forces Day (Honduras)
Egyptian Naval Day (Egypt)
Indian Police Commemoration Day (India)
International Day of the Nacho
National Nurses' Day (Thailand)
Ndadaye Day (Burundi)
Overseas Chinese Day (Taiwan)
Trafalgar Day (the British Empire in the 19th and early 20th century)
October 22
Fechner Day (International observance)
International Caps Lock Day
International Stuttering Awareness Day
Jidai Matsuri (Kyoto, Japan)
National Santri Day (Indonesia)
Wombat Day (Australia)
October 23
Aviator's Day (Brazil)
Chulalongkorn Day (Thailand)
Day of the Macedonian Revolutionary Struggle (Republic of Macedonia)
Liberation Day (Libya)
Mole Day (International observance)
National Day (Hungary)
Paris Peace Agreement Day (Cambodia)
October 24
Azad Kashmir Day (Pakistan)
Day of Special Forces of the Armed Forces (Russia)
Food Day (United States)
Independence Day (Zambia)
Suez Day (Egypt)
United Nations Day (International observance)
World Development Information Day
World Polio Day
October 25
Armed Forces Day (Romania)
Constitution Day (Lithuania)
Customs Officer's Day (Russia)
Day of the Basque Country (Basque Country)
Retrocession Day (Taiwan)
Sovereignty Day (Slovenia)
Thanksgiving Day (Grenada)
The Hallowing of Nestorius (Nestorian Christianity)
October 26
Accession Day (Jammu and Kashmir)
Angam Day (Nauru)
Armed Forces Day (Benin)
Intersex Awareness Day (International observance)
National Day (Austria)
October 27
Black Cat Appreciation Day (United Kingdom)
Černová Tragedy Day (Slovakia)
Flag Day (Greece)
Independence Day (Saint Vincent and the Grenadines)
Navy Day (United States) (unofficial, official date is October 13)
World Day for Audiovisual Heritage
October 28
Day of the Establishment of an Independent Czecho-Slovak State (Czech Republic and Slovakia)
International Animation Day
Ohi Day (Greece, Cyprus)
Prefectural Earthquake Disaster Prevention Day (Gifu Prefecture, Japan)
Youth Pledge Day (Indonesia)
October 29
Coronation Day (Cambodia)
Cyrus the Great Day (Iran)
National Cat Day (United States)
Republic Day (Turkey)
World Stroke Day
October 30
Anniversary of the Declaration of the Slovak Nation (Slovakia)
Day of Remembrance of the Victims of Political Repressions (former Soviet republics, except Ukraine)
Indonesian Banknote Day (Indonesia)
International Orthopaedic Nurses Day
Mischief Night (United States and Canada)
Beggars Night (certain regions of the United States)
Devil's Night (Michigan, United States)
Thevar Jayanthi (Thevar community, India)
October 31
Start of Allhallowtide October 31 – November 6
The first day of the Day of the Dead, celebrated until November 2 (Mexico)
Día de la Canción Criolla (Peru)
Eve of Winter, the eve of the first day of winter in the Northern hemisphere:
Allantide (Cornwall, United Kingdom)
Halloween (English-speaking countries, also in other locations)
Hop-tu-Naa (Isle of Man, United Kingdom)
Samhain in the Northern Hemisphere, Beltane in the Southern Hemisphere; begins on sunset of October 31 (Gaels, Welsh people and Neopagan Wheel of the Year)
Girl Scouts Founders Day (United States)
King Father's Birthday (Cambodia)
National Unity Day (India)
Reformation Day (Slovenia, parts of Germany, Chile, El Salvador, Dominican Republic, Evangelical Churches and Lutheran Churches)
Saci day (Brazil)
World Savings Day
Statehood Day Nevada, United States
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