The Haus der Kunst in Munich is the unlikely setting this winter for a celebration of German princely patronage, the first of its kind and consciously modelled on the famous Washington 'Treasure Houses of Britain' exhibition of 1985. More than thirty noble families, or their foundations, have lent some 350 objects, from St Elizabeth's arm-bone in a gem-set silver-gilt reliquary, from Schloss Sayn, to paintings by Blinky Palermo from the Wittelsbach collection.

A joyous diversity in guest curator Wilfried Rogasch's selection, and the generous collaboration of the owners, has brought together personal, domestic, sacred and ceremonial treasures from two and a half millennia. Romantic, waterbound castles and palaces across former West Germany have yielded little-known furniture by Roentgen; Sevres and Berlin porcelain; black-figure and red-figure vases; Italian drawings; portraits ranging from Cranach's Prince and Princess of Anhalt to Laszlo's Philip of Hesse; and Old Master paintings, such as Rembrandt's Diana and Actaeon, lent by the Prince Salm-Salm. Striking goldsmiths' work, mostly from German workshops, is memorable for its scale and complexity of design. Schloss Glucksberg, north of Kiel, has lent a group of portraits of 1829, while Schloss Wolfegg, far to the south in Baden-Wurttemberg, has lent drawings by the Holbeins, father and son.

The choices were driven not merely by connoisseurship but were intended to express the character and strongly German quality of five centuries of patronage. Renaissance works of art, religious objects and images and family portraits give a distinctive flavour. Apart from a mid-eighteenth-century state bed and a tapestry, there are virtually no textiles, and little jewellery apart from Le beau Sancy, a dazzling and large diamond, cut around 1600 and lent by the Hohenzollerns.

Although the exhibition has little supporting material of the kind familiar in British art shows--no family trees, for example, and no maps--a large screen shows views of architecture and interiors. These enticing images are repeated in the richly illustrated book, also by Wilfried Rogasch, which includes a ninety-page gazetteer of the lenders' houses, with brief histories, and web sites for would-be visitors. The objects are listed briefly in an appendix, with measurements. There is no bibliography; this is truly a celebration, rather than a scholarly show freighted with references.

Familiar names--Prince Ernst August of Hanover, Gloria Princess of Thurn and Taxis, and Moritz, Prince of Hesse, for example--are present. Their collections, such as the ceramics and antiquities from Schloss Fasanerie and the Thurn and Taxis contemporary commissions, have been published and shown from time to time. But most princely collections have remained private, partly because of the distinctive social character of Germany since the end of World War I, when the monarchy was abolished. A city-based culture has in effect turned its back on the former ruling families, many of whom are still land owners on a large scale; now, with rising taxes and falling income from agriculture, their collections are coming under pressure from the auction houses.

Sales from Schloss St Emmeram, Regensberg; from the Prince of Hanover's collection; from the Wettin family treasures; and from the Prussian royal family, to mention only the high-profile disposals, have marked the past twenty years. The German state has little statutory protection in place, and Bavaria in particular has mounted some heroic open-market rescue operations. Splendid boxes, silver and porcelain sold from Schloss St Emmeram in 1993 have been acquired and put on show in a branch of the Bavarian National Museum at the Schloss itself, although this is currently closed because of funding problems.

The strong aesthetic of the monumental 1937 Haus der Kunst, with its red marble floors and towering halls, as well as budgetary constraints, has precluded any elaborate display techniques, so that the objects are allowed generous space, with adequate labelling and simple lighting. Most objects are grouped by theme and material, so that an early room shows heraldic manuscripts and insignia, another stained glass, reliquaries, vestments and even an intricately carved set of choir stalls of the 1580s from the minster at Schloss Salem. A ravishing selection of early drawings, most not reproduced in the accompanying book, from the collection at Schloss Wolfegg include a design for a nautilus cup by Holbein the Younger, a landscape study by Perino del Vaga and engravings by Pollaiuolo, Schongauer, Durer and Cranach.

The visual contrast is most striking in the central hall, where Adriaen de Vries's bronze Watchmen of around 1620 are uneasily juxtaposed with C-prints by Thomas Ruff, Candida Hofer and Rineka Dijkstra, recent Thurn and Taxis commissions. Removed for the first time from the Schaumburg-Lippe mausoleum in the Martinskirche, Stadthagen, Lower Saxony, De Vries's figures cluster below a towering Christ on a two-part painted wood base that recalls, rather than replicates, the monument's original stone and bronze structure.