In April 2003 there has been an important step taken in that longlasting process, which had dominated the development of east-central European states of transition for about a decade - the reshaping of the Ancient Europe in juristic sense. The diplomatic event, which had taken place in the surrounding of the Acropolis, was obviously symbolic, because at that historic place the western legal tradition has been united with the legal tradition of Eastern Europe. But the newly constructed constitutional unity is not unknown, there have already been historical models in legal sense, if one takes a look at the watersheds of the legal development in Europe.

It is a common knowledge, that before the age of nationbuilding in the 19th century, the Roman an Canonic law based ius commune was acknowledged by the courts through Europe. In the 19th century this legal community did not came to an end abruptly, instead of the ius commune a finely spun net of communication of scholars has been built up. That was the way, how legal knowledge was transferred between the European legal systems.

This article focuses on the impacts of this scientific communication on the modernisation of Hungarian law. After reviewing the stand of the research and some methodological issues, the transfer of legal ideas is discussed in four stages: during the age of the enlightment (1770-1795), in the Age of Reform (1825-1848), during the Absolutism (1849-1861-1867) and in the Age of Dualism (1867-1918). The most important lines of exchange, the so-called liaisonmen and the recipients (commissions of codification, board of editors of periodicals, the Hungarian Academy of Sciences and the professional associations of lawyers) are outlined in these four periods, in order to replace the former Dogmengeschichte-oriented topics by theses based on Sozialgeschichte.

In this paper the way of the establishment of a 19th century- legal system is shown, which could not have been destroyed basically, when constitutional guarantees of the due process had been perished by the nationalistic and communist ideology. In the age of the reconstruction of those guarantees in the east central European states of transition, these elements had been referred to, so that at the dawn of the new year thousand the historic cognitions are of novel importance.