May 1, 2010 Kentucky Derby
May 3, 2010 World Press Freedom Day
May 4, 2010 Kent State Shootings Remembrance
May 4, 2010 Rhode Island Independence Day
May 4, 2010 Primary Election Day
May 5, 2010 Cinco de Mayo
May 6, 2010 National Nurses Day
May 6, 2010 National Day of Prayer
May 7, 2010 Truman Day observed
May 8, 2010 Time of Remembrance and Reconciliation for Those Who Lost Their Lives during the Second World War
May 8, 2010 World Migratory Bird Day
May 8, 2010 Victory in Europe Day
May 10, 2010 Confederate Memorial Day
May 11, 2010 Primary Election Day
May 12, 2010 International Nurses Day
May 13, 2010 Ascension Day
May 15, 2010 International Day of Families
May 15, 2010 Peace Officers Memorial Day
May 15, 2010 Armed Forces Day
May 15, 2010 Preakness Stakes
May 17, 2010 World Information Society Day
May 19, 2010 Emergency Medical Services for Children Day
May 21, 2010 World Day for Cultural Diversity for Dialogue and Development
May 21, 2010 National Defense Transportation Day
May 22, 2010 International Day for Biological Diversity
May 22, 2010 National Maritime Day
May 22, 2010 Harvey Milk Day
May 25, 2010 African Liberation Day
May 25, 2010 National Missing Children's Day
May 27, 2010 Day of Vesak
May 29, 2010 International Day of United Nations Peacekeepers
May 30, 2010 Trinity Sunday
May 31, 2010 World No Tobacco Day
May 31, 2010 Memorial Day
May 31, 2010 Jefferson Davis' Birthday