This thesis examines the various ways that the perception of bankers and banking in Florence changed from the 13th to the 15th century. This topic is broken down into three categories, scholastic attitude, law, and public image, and utilizes a socio-intellectual style of historical inquiry. The purpose of this study is to demonstrate that the positive acceptance of banking from a formerly profane vocation was due to a more advanced understanding of industry and economics, a more relativistic interpretation of theological and juridical sources, and an aggressive campaign by the humanists to redefine moral values and to reshape the Florentine culture and urban landscape in order to bring esteem and power to the elite bankers. Many cultural themes are examined, including public attitudes toward wealth, profit, honor, and nature. Sociological analysis reveals the impact of banking on Florentine society, from rural farmers, middle-class artisanal workers, and members of the elite ruling class, as well as its relationships with ecclesiastical and civic institutions. Various types of banking are also investigated, including international exchange, money lending, pawn brokerage, and public finance. Finally, a variety of types of bankers are featured in this study, from the elite banking families such as the de' Medici, smaller scale bankers including the Jewish lenders, and the public lending institution known as the monte di piet. Sources in this study range from ancient Greek and Roman philosophical texts, biblical sources, medieval moral and ecclesiastical treatises, and literary and intellectual discourses from the Renaissance. Secondary sources play an instructional and inspirational role in the development of this study, particularly the works of Richard A. Goldthwaite, Odd Langholm, and Lauro Martines. This study examines the Florentine perception of banking from a wide range of historiographical perspectives in order to trace the forces and agents that were responsible for its dramatic shift, from inexorable disapproval to dignified civic and cultural preeminence.