https://doi.org/10.1515/9783110647662-018 Elisabeth Fraser Heinrich Friedrich von Diez and Costumes turcs An Ottoman Costume Album in Prussia In 1858 the British Museum purchased an album of Ottoman costume paintings that reportedly had at one time belonged to Heinrich Friedrich von Diez. Costumes turcs contains 264 colorful images, in two bound volumes, representing dress in the Ot- toman Empire. According to an English inscription on an opening page of the al- bum, it was acquired by Diez during his diplomatic residence in Istanbul. An unu- sually elaborate album and an intriguing object in its own right, though it has received scant attention from scholars, Costumes turcs exemplifies the kind of acci- dental cross-cultural collaboration typical of costume albums: traveling from Istan- bul to Berlin and then London, it was elaborated by successive owners, who added to its material state and reinterpreted and redefined it. One reason for the British Museum’s interest in the album was its prestigious provenance. The inscription, signed by Sir Frederic Madden, the nineteenth-century Keeper of Manuscripts, indicates as much: »These drawings have been stated to have been executed by order of the Sultan for General Diez, Prussian Ambassador at Constantinople, at the time of Frederick II.« 1 Madden’s note connects the volumes to an important collector and ambassador, Diez, and through him, to a celebrated Prussian king and an Ottoman sultan. Subsequent catalogue entries for the two- volume manuscript all take Diez’s ownership as a matter of fact. Like many European ambassadors to the Ottoman Empire, Diez actively collect- ed manuscripts during his time in the Ottoman capital. Diez was nonetheless unu- sual among diplomats both for his pro-Ottoman inclinations and devotion to Otto- man culture, as well as for the avidity and seriousness of his collecting activity. In Istanbul and later in Berlin, Diez amassed a large collection of Oriental manuscripts, 410 of which are now in the Staatsbibliothek, along with over 430 Occidental manu- scripts and a large library of about 17.000 print books. 2 He also purchased prints, paintings, coins, and maps, among other things, though little remains of this part of his collection. Among the objects in his collection, Diez seems to have distinguished || 1 The notation is signed »F.M.« At first sight, these initials confusingly appear to be »J.M.«, but a look at Frederic Madden’s papers in the archives of the British Library confirm without doubt that this is his monogram. 2 See Christoph Rauch: The Oriental Manuscripts and Albums of Heinrich Friedrich von Diez and the Perception of Persian Painting in His Time. In: The Diez Albums. Contexts and Contents. Ed. By Julia Gonnella, Christoph Rauch a. Friederike Weis. Leiden, Boston 2017, pp. 74–106.