Despite its elusive character, the rule of law is a fundamental feature of American government. Rule of law ideals can be traced back to the ancient times and primarily to the British legal and political philosophy (starting with the Magna Carta 1215) that heavily influenced the formation of the US Constitution. Due process of law, enshrined in the Fifth and Fourteenth Amendments, is the modern variant of rule of law principles. This paper describes the most important events and conflicts in the development of due process jurisprudence, revealing unique circumstances and concerns that shaped America’s own legal system. It shows the evolution of the understanding of the due process of law by focusing on the development of two interdependent strands of due process (procedural and substantive) and explains how American due process has deviated from its (British) rule of law roots.