International Day for the Abolition of Slavery 2 December

"The International Day for the Abolition of Slavery, 2 December, recalls the date of the adoption, by the General Assembly, of the United Nations Convention for the Suppression of the Traffic in Persons and of the Exploitation of the Prostitution of Others (resolution 317(IV)of 2 December 1949)." 

http://www.antislavery.org/english/