Abraham Lincoln had the greatest impact of any individual in advancing the position of African Americans in the USA, how valid is this view of the years 1776-1877?

INSTRUCTIONS: ULTIMATELY, ARGUING THAT IT IS THE CASE HE HAD THE GREATEST IMPACT EVERY DECADE MUST BE COVERED 3 PRIMARY SOURCES NEED TO BE USED, EMBEDDED – WITH EVALUATION OF LIMITATIONS AND USES OF SOURCE IN SUPPORT OF ARGUMENT (THAT HE HAD THE GREATEST IMPACT) ( ONE SOURCE INCLUDED IN ATTACHMENTS THAT CAN BE USED)  […]