Court society in Berlin includes the German "higher" and "lower" nobility, with the exception of the so-called Fronde, who proudly absent themselves from it; the Ministers; the diplomatic corps; Court officials; and such members of the burghertum, or middle class, as hold offices which entitle them to attend court. The wives, however, of those in the last category are not "court-capable" on this account, nor is the middle class generally, nor even members of the Imperial or Prussian Parliaments as such. Members of Parliament are invited to the Court's seasonal festivities, but as a rule only members of the Conservative parties or other supporters of the Government. The nobility, as in England, is hereditary or only nominated for life, and the hereditary nobility is divided into an upper and lower class. To the former belongs members of houses that were ruling when the modern Empire was established, and, while excluding the Emperor, who stands above them, includes sovereign houses and mediatized houses. Some of the ancient privileges of the nobility, such as exemption from taxation, and the right to certain high offices, have been abolished, but in practice the nobility still occupy the most important charges in the administration and in the army. The privileges of the mediatized princes consist of exemption from conscription, the enjoyment of the Principle called "equality of birth," which prevents the burgher wife of a noble acquiring her husband's rank, and the right to have their own "house law" for the regulation of family disputes and family affairs generally. No increase to the high nobility of Germany can accrue as no addition will ever be made to the once sovereign and mediatized families. With the exception of these houses the rest of the German nobility, hereditary and non-hereditary, is accounted as belonging to the lower nobility. That part of the German aristocracy who refuse to go to court, and are accordingly called by the name Fronde, first given to the opponents of Cardinal Mazarin, in the reign of Louis XIV, consist chiefly of a few old families of Prussian Poland, Hannover (the Guelphs), Brunswick, Nassau, Hessen, and other annexed German territories, and of some great Catholic houses in Bavaria and the Rhineland. Their dislike is directed not so much against the Empire as against Prussia. The Kulturkampf had the effect of setting a small number of ancient Prussian ultramontane families against the Government.