World Sparrow Day

World Sparrow Day

HIV.gov

National Native HIV/AIDS Awareness Day (United States)

UN French Language Day

International Francophonie Day (Organisation internationale de la Francophonie), and its related observances:
UN French Language Day (United Nations)

International Day of Happiness

International Day of Happiness (United Nations)

Farm Animal Rights Movement

Great American MeatOut (United States)

March 20 (Eastern Orthodox liturgics)

Christian feast day:
March 20 (Eastern Orthodox liturgics)

Wulfram of Sens

Christian feast day:
Wulfram

Michele Carcano

Christian feast day:
Michele Carcano

Martin of Braga

Christian feast day:
Martin of Braga

María Josefa Sancho de Guerra

Christian feast day:
María Josefa Sancho de Guerra

Józef Bilczewski

Christian feast day:
Józef Bilczewski

John of Nepomuk

Christian feast day:
John of Nepomuk

Herbert of Derwentwater

Christian feast day:
Herbert of Derwentwater

Cuthbert

Christian feast day:
Cuthbert of Lindisfarne

Clement of Ireland

Christian feast day:
Clement of Ireland