Phillis Weathley was an African slave (emancipated later in life) and poet. She was captured and brought to the colonies as a slave. However, despite her position, she received an extensive education which allowed her to become a successful and renowned poet.
This is the main reason why she played an important role in abolishing slavery. Weathley's talent and intelligence were evidence that African people were just as intelligent as Europeans. It also showed that any apparent deficiencies of African people were due to a lack of education, and therefore, could be remedied if they were to be granted their freedom and equal rights.