Complex sentence: The African slave trade was outlawed in 1807, by a law passed jointly in the United States of America and the United Kingdom, the applicable UK act was the Abolition of the Slave Trade Act and outlawed slavery throughout the British Empire.
Split into simpler sentences: The African slave trade was outlawed in 1807, by a law passed jointly in the United States of America and the United Kingdom. The applicable UK act was the Abolition of the Slave Trade Act and outlawed slavery throughout the British Empire.