My dissertation examines the transmission and establishment of the institution of slavery from medieval Iberia into the expanding Spanish Empire and its subsequent development. This involves understanding the dynamic interactions between the law, imperial institutions, slave owners, and the enslaved. I embarked upon this subject in response to a lacuna of historical knowledge of the transition and development of slavery as it moved between the Iberian Kingdoms and took root in the expanding Atlantic Empires. Without understanding the medieval background of imperial law it is impossible to understand the particular development of the institution of slavery in Spanish America. / History