Byzantine law was essentially a continuation of Roman law with increased Orthodox Christian and Hellenistic influence. Most sources define Byzantine law as the Roman legal traditions starting after the reign of Justinian I in the 6th century and ending with the Fall of Constantinople in the 15th century. Although future Byzantine codes and constitutions derived largely from Justinian's Corpus Juris Civilis, their main objectives were idealistic and ceremonial rather than practical. Following Hellenistic and Near-Eastern political systems, legislations were tools to idealize and display the sacred role and responsibility of the emperor as the holy monarch chosen by God and the incarnation of law "nómos émpsychos", thus having philosophical and religious purposes that idealized the perfect Byzantine king.

Though during and after the European Renaissance Western legal practices were heavily influenced by Justinian's Code (the Corpus Juris Civilis) and Roman law during classical times, Byzantine law nevertheless had substantial influence on Western traditions during the Middle Ages and after.

The most important work of Byzantine law was the Ecloga, issued by Leo III, the first major Roman-Byzantine legal code issued in Greek rather than Latin. Soon after the Farmer's Law was established regulating legal standards outside the cities. While the Ecloga was influential throughout the Mediterranean (and Europe) because of the importance of Constantinople as a trading center, the Farmer's Law was a seminal influence on Slavic legal traditions including those of Russia.