What was Max Weber's contribution to Du Bois?

The contributions of W. E. B. Du Bois have recently been acknowledged for their pioneering role based on recent research on the history of sociology and African American contributions to the discipline’s origin in the United States. An influential work on the topic is The Scholar Denied (2015) by Aldon Morris.
DuBois earned a doctorate at Harvard University and knew Max Weber while studying in Germany in the 1890s. His own research on African American communities in Pennsylvania, which included evidence that was scientifically selected and evaluated, resulted in The Philadelphia Negro, published in 1897. While teaching at Atlanta University, a historically black university, DuBois created a sociology research program.
The question of who influenced whom is one that Morris addresses. Traditional histories name Weber as Du Bois’s mentor from their days in Germany together. However, Weber read and mired DuBois’s work, as indicated in his letters regarding The Souls of Black Folk. At Weber’s invitation, DuBois wrote and published "Die Negerfrage in den Vereinigten Staaten" (1906) in the journal Weber edited, Archiv für Sozialwissenschaft and Sozialpolitik. The theories of race that Du Bois put forward in it, specifically the identification of the American racial caste system, influenced Weber's ideas about stratification as caste system.
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