Roman law evolved from unwritten customs under kings to a codified system that shaped modern civil law. From the Twelve Tables to Justinian’s Corpus Juris Civilis, it reflected shifts in power, social protest, and legal reform. Its legacy endures in legal systems worldwide.

Believed to be the world’s oldest written legal code, the Code of Ur-Nammu—dating back to around 2100 BCE in ancient Mesopotamia—opens with a striking first law: "If a man commits a murder, that man must be killed." This early declaration of capital punishment marks a foundational moment in legal history, illustrating how justice and social order were enforced nearly 4,000 years ago. The law reflects retributive justice principles and highlights the emergence of state-adminis