The book that helped draw attention to the abolisionist cause in Great Britain was called "The Interesting Narrative of the Life of Olaudah Equiano, Or Gustavas Vassa, The African."
The book is about Equiano's time in slavery, his multiple attempts at becoming an independent man through studying his Bible, his eventual success at becoming independent and his life after. It played a large role in altering the British's opinon towards slavery.