Truth be told, these legal codes were not very different from many issued in England and elsewhere during the same period. Like his Sicilian counterparts, Henry II of England was in frequent conflict with the popes (and with Thomas Becket), and some of his legislation reflected this, as did Frederick's. However, Frederick's laws clearly had to take into account the cultural diversity of his southern Italian realm, which even in 1231 still had sizeable Muslim, Jewish and Byzantine (Orthodox) populations. (There are thought to have been Maliki Islamic influences in the laws of Norman Sicily.) The Constitutions also considered certain differences between the Frankish Law of the Normans and the Longobardic Law of the Lombards and Germans, important factors in nobiliary matters such as land inheritance and the designation of heirs.

A lengthy summary is not possible here, but let's outline a few characteristics of the Constitutions.

Not only did the new legal code reinforce royal authority over the nobility and the use of resources, its references to heresy and to Roman canon law effectively formed the groundwork for the Kingdom of Sicily evolving into a predominantly Roman Catholic country within a few decades. By the War of the Vespers in 1282, just three decades after Frederick's death, most Muslims and Orthodox had converted to Catholicism, even if a few isolated pockets of Byzantine influence remained for some time afterward.

Like England's Magna Carta, the Constitutions of Melfi made a speedy judgement the right of civil litigants and even criminal defendants. This is one of the things lacking in Italy today, when civil cases can take many years to run their course.

Juridical procedures are clearly established, while practices such as trial by combat (knights duelling to win a legal dispute) are essentially abolished.

The idea that justiciars (district judges) could not hear cases in lands where they held feudal estates was a novel idea, prescient to modern conflict-of-interest statutes.

Jews, but not Christians, could practice usury (though Judaic law formally prohibits this).

A man of the kingdom could divorce his wife if adultery were proven, while the same practice among Muslim presumably existed as well.

The sale of toxic foods and potions was outlawed, and the burning or disposal of certain toxic substances was prohibited – flax and hemp couldn't be soaked in water near towns and yew (which can emit toxins) could not be disposed in rivers.

Theft, trade and even the comportment of physicians are considered at length. So is cattle rustling, coin shaving and the forgery of documents.

The law on divorce, though clearly weighted in favor of the husband, may seem innovative. In fact, divorce had existed, in one form or another, among Christians since the earliest times. It was only later that the Catholic hierarchy, influencing European monarchs, attempted to suppress the practice. Italy was one of the last major European nations to legalise divorce (which is still illegal in, for example, Malta).

Extensive legislation is devoted to women's rights, and to those of children. The statute defining penalties for mothers who prostitute their daughters implies that this was a fairly widespread problem, but there are severe penalties for rape too, and violence toward prostitutes.

In a precedent which would influence the laws of Scotland and Spain, daughters were allowed to succeed to feudal property and titles of nobility in the absence of male heirs – a practice which survived into the nineteenth century (the end of feudalism in 1812) and (as regards titles) 1926. This is the origin of the so-called Sicilian Succession.

A few laws seem less enlightened. Adultery itself is a crime, but a husband might not be punished if he kills his adulterous wife and her lover immediately upon catching them in the sexual act. A peasant who strikes a knight or noble might have the offending hand chopped off unless he can prove that he acted in self defense.

Capital punishment existed and is mentioned, but some scholars have suggested that the term as used in the Constitutions sometimes refers to loss of citizenship rather than loss of one's life. Translation of several Latin words is debated; the term serf may be more accurate than slave in certain statutes, actual slavery being all but unknown in the Kingdom of Sicily by 1231.

It is in the Constitutions that Frederick establishes that only the son of a knight or noble may become a knight unless, in the case of a man of common birth, royal assent is granted. In practice, such assent was probably obtained quite often, yet the law is a clear attempt to restrict entry into the aristocratic class.

There are also attempts to regulate local government and the construction of towers and castles, probably to discourage the development in southern Italy of communities similar to the northern Italian city-states which challenged Frederick's authority as Holy Roman Emperor. Throughout the Constitutions it is abundantly clear that Frederick exercised an absolute authority in the Kingdom of Sicily that he did not enjoy in the northern Italian and German regions under his crown.

No legal code is perfect, but Frederick's was significantly evolved for its time. Perhaps the best scholarly analyses of the Constitutions of Melfi published in English are those of David Abulafia and James Powell. They are nothing if not insightful. It has been suggested that perhaps Frederick was a deist who looked to enlightened "natural law" for some of his inspiration.

Frederick's legislation, built upon that of his predecessors and existing legal codes - and perhaps a few novel ideas - serves to remind us that, for a brief moment, the law ruled supreme in Sicily.

About the Author: One of Sicily's foremost historians, Luigi Mendola is the author of two books.