<human>:  How did slavery start in the United States?
<bot>: The first slaves in the United States were brought over by the Spanish in the 16th century. They were African slaves who were captured by the Spanish and sold into slavery. Slavery in the United States began with the African slave trade, but it also included other forms of slavery such as indentured servitude, debt bondage, and peonage. Slavery was abolished in 1865 with the 13th Amendment to the United States Constitution.