The body of law developed in Rome between about 150 bc and 250 ad and codified by the Emperor Justinian in 529 in his Corpus Juris Civilis (‘Body of Civil Law’). Roman law re-emerged in the 11th century as a popular subject of study in the Italian universities; later it evolved into the common core of the civil law (or Romano-Germanic law) family of legal systems, which established itself in the lands of the Holy Roman Empire. The ideas of Roman law were dominant in the French Code Napoléon, adopted in 1804, and in later civil codes adopted in Germany, Switzerland, and Austria. The codification movement appealed to the perceived higher rationality of Roman law as providing a logically consistent set of principles and rules for solving disputes.