Slavery has existed in various forms for thousands of years. It began in Africa before European colonization and spread globally as the Portuguese, Spanish, English, French and others engaged in the transatlantic slave trade between the 15th and 19th centuries. Millions of people were taken from Africa and enslaved in the Americas. Slavery was gradually abolished in the late 18th and 19th centuries, starting with declarations in Vermont in 1777 and Britain banning the slave trade in 1807, but it continued in other forms into the early 20th century in some places. Slavery stripped people of rights and freedoms and legally classified them as property without kinship or protections.