International Day For Abolition Of Slavery 2021 Date is 2nd December and it has been celebrated since 1986 as announced by the United Nations General Assembly. Here are some important specifications you need to know about International Day for the abolition of slavery 2021-date, its history, theme, facts, and the significance of the day. 🙏🏻 International Day for the Abolition of Slavery 2021: Know Date, History, Significance, Theme and Facts About This Important Yearly Event.