One the most important facts in the Spanish ancient history was the conquest of the Iberian Peninsula by the Roman Empire. The same legal system was used in the whole Roman Empire (with some peculiarities in each territory) and went through an elaboration process that started and finished with the empire itself, for more than 1,200 years.
The beginning of that system was the “mores maiorum” in which Pontiffs had a juridical monopoly. During the VI Century B.C., a series of laws called “Lex Regia” gave some power to kings, and at the middle of the V Century B.C: appeared the “Law of the XII Tables”, that stated the interpretation of the “mores maiorum” to the Law “prudence”, called the Jurisprudence. Other important periods of Roman law were the “Period of Principality”, and the “Juridical Order of Dominado”, from which different juridical recompilations have been retrieved.
The Provincial Rights of Hispania were configured through a “Lex Provinciae”, a law by which the Roman Senate established the juristic situation of all lands under the Roman Empire. Also, Hispania was given special laws such as the “Laws of Colonies and Municipalities” and the “Law of Osuna”.
The Roman Empire gave specific laws to Hispania due to the commercial interest of some lands, such as provincial laws devoted to mines. Other relevant dispositions were found, such as the Edict that gave freedom to slaves of some parts of the country, giving them the property of lands they cultivated as slaves. (Pensamiento Español 2016)