Phillips systematically hunted down and revealed plantation records and unused manuscript sources. An example of pioneering comparative work was "A Jamaica Slave Plantation" (1914). His methods and use of sources shaped the research agenda of most succeeding scholars, even those who disagreed with his favorable treatment of the masters. After the Civil Rights Movement of the 1960s historians turned their focus away from his emphasis on the material well-being of the slaves to the slaves' own cultural constructs and efforts to achieve freedom.