This dissertation contends that conventional historiography of African-European encounters has systematically obscured Africa's pivotal role in the late fifteenth and sixteenth centuries, a period crucial to shaping the modern Atlantic world. The research demonstrates that rather than passive recipients of European influence, Africans were active agents who initiated, negotiated, and sometimes directed cross-cultural, intellectual, socioeconomic, and political exchanges. To defend this claim, the study examines how evolving ideas about religious, racial, and political identities influenced early modern knowledge production and sociopolitical relations. It uses three interconnected case studies from the late fifteenth and sixteenth centuries across Africa, Europe, and the Americas: (1) the 1534 encounter between Ethiopian monk Abba Mika’el and Reformers Martin Luther and Philipp Melanchthon in Wittenberg; (2) the origins of race-based enslavement around 1516 in the Americas, which developed into racialized chattel slavery in the United States; and (3) the Kingdom of Kongo's conversion to Christianity in 1483 and its subsequent religious and diplomatic ties with Portugal and Rome. These cases are significant because the ideological and cultural shifts behind them were key to the emergence of the modern Atlantic world. The research poses two main questions: how do these cases challenge existing scholarship that overlooks earlier African-European encounters, especially in the fifteenth and sixteenth centuries? And how might global development and historical records have differed if equitable partnerships had continued without racialized slavery? While the second question remains hypothetical, the first is practical, necessary, and the primary focus of this work. This dissertation challenges scholars to rethink existing narratives of early modern African-European interactions and reconsider Africa's role. Using the "sea/oceanic method," which integrates cultural, economic, political, social, and intellectual exchanges across the Atlantic, this work avoids a binary Eurocentric or Afrocentric view while highlighting marginalized narratives. It contributes to fields such as intellectual history, early modern studies, cultural studies, Atlantic studies, and Reformation history by uncovering the complex, cross-cultural nature of knowledge creation and exchange, tracing the evolution of ideas and their sociocultural impacts, and centering marginalized narratives to offer a more accurate picture of early African-European engagements that shaped the modern Atlantic world.