German law was subject to many influences over the centuries. Roman law was the first civilized jurisprudence within the borders of German influence and prevailed in the parts of Germany belonging to the Roman Empire until the end of Roman dominion. In Medieval times, derivatives of Frankish law were common, until the first universities and legal scientists reinstated Roman Law as set by Justinian I. in the Corpus iuris civilis. It became common law (Gemeines Recht) in large parts of the German-speaking world and prevailed far into the 19th century. As the Holy Roman Empire was composed of countless little territorial entities, the laws varied very much, according to local traditions and religions.

Prussia made an effort of installing an all-new law with the Preußisches Allgemeines Landrecht in the 18th century which, although never actually finished, had - and has - a great influence on later works. After the French Revolution, revolutionary ideas and Naponéons Code Civil strongly influenced the German legal tradition. With the forming of the Deutsches Reich in 1871, a great wave of legal standartization set on, beginning with criminal law and processual law and culminating in the Bürgerliches Gesetzbuch (Book of Civil Law) after over twenty years of creative process.

However, the various states always maintained their own laws to an extent and, in modern federal Germany, still do. This came to an end during the Nazi dominion when law was for the most part set by the Führer, the party and the judges and legal scientists loyal to them, which created a totalitarian law with strong elements of racism and anti-semitism. After the war, the two newly emerged German states tried to pick up the pieces in their own way: the democratic West Germany continued the legal traditions of the first republic, while the socialist/communist East Germany tried to install new laws strongly by communist and socialist ideology. With the reunification of the two parts, West German law was set in force for the most part.

A fairly recent development is the influence of European law which aims to harmonize laws in the various states of the European Union, so that a lot of the legal developments are taken out of the hand of the federal government and are decided in Brussels instead, where Germany has its own influence on the process along with the other members. Still German law is strongly influenced by federalism, and the individual states (Länder) each have their own responsibilities and particular laws, which at times is somewhat inefficient, but on other occasions takes care of regional specialities.

German legal tradition has in turn influenced many other countries. Just to name a few, the legal systems of Japan, the Republic of Korea and the Peoples Republic of China are to some extent based on German law.