Editing Frederick Barbarossa (section)

==Frederick and the Justinian code==
The increase in wealth of the trading cities of northern Italy led to a revival in the study of the [[Justinian Code]], a Latin legal system that had become extinct centuries earlier. Legal scholars renewed its application. It is speculated that [[Pope Gregory VII]] personally encouraged the Justinian rule of law and had a copy of it. The historian [[Norman Cantor]] described [[Corpus Juris Civilis]] (Justinian Body of Civil Law) as "the greatest legal code ever devised".<ref>{{cite book |last1=Cantor |first1=Norman F. |year=1993 |title=The Civilization of the Middle Ages |url=https://books.google.com/books?id=5tQYAAAAYAAJ&q=%22greatest+legal+code+ever%22 |location=New York |publisher=HarperCollins |page=309 |isbn=0060170336 |access-date=24 September 2016 }}</ref> It envisaged the law of the state as a reflection of natural moral law, the principle of rationality in the universe. By the time Frederick assumed the throne, this legal system was well established on both sides of the Alps. He was the first to use the availability of the new professional class of lawyers. The Civil Law allowed Frederick to use these lawyers to administer his kingdom in a logical and consistent manner. It also provided a framework to legitimize his claim to the right to rule both Germany and northern Italy. In the old days of Henry IV and Henry V, the claim of [[divine right of kings]] had been severely undermined by the [[Investiture controversy]]. The Church had won that argument in the common man's mind. There was no divine right for the German king to also control the church by naming both bishops and popes. The institution of the Justinian code was used, perhaps unscrupulously, by Frederick to lay claim to divine powers.<ref>{{harvp|Cantor|1969|pp=340–342}}</ref>

In Germany, Frederick was a political realist, taking what he could and leaving the rest. In Italy, he tended to be a romantic reactionary, reveling in the antiquarian spirit of the age, exemplified by a revival of classical studies and Roman law. It was through the use of the restored Justinian code that Frederick came to view himself as a new Roman emperor.<ref>{{harvp|Davis|1957|p=332}}</ref> Roman law gave a rational purpose for the existence of Frederick and his imperial ambitions. It was a counterweight to the claims of the Church to have authority because of divine revelation. The Church was opposed to Frederick for ideological reasons, not the least of which was the humanist nature found in the revival of the old Roman legal system.<ref>{{harvp|Davis|1957|p=324}}</ref> When [[Pepin the Short]] sought to become king of the Franks in the 8th century, the church needed military protection, so Pepin found it convenient to make an ally of the pope. Frederick, however, desired to put the pope aside and claim the crown of old Rome simply because he was in the likeness of the great emperors of old, who tended to have a domineering role over the church, [[Caesaropapism]]. [[Pope Adrian IV]] was naturally opposed to this view and undertook a vigorous propaganda campaign designed to diminish Frederick and his ambition. To a large extent, this was successful.<ref>{{harvp|Davis|1957|p=325}}</ref>