Gotthard Kettler was elected coadjutor (co-ruler and successor) of the master of the Teutonic Order in Livonia in July 1558. The Order in Livonia was in deep crisis because of the war with the Muscovy, and the old master Wilhelm von Fürstenberg was unable to manage it. In these circumstances Kettler strived with all methods for the office of the master. The chronicles of the period date the final change in the leadership of the Order as of September 1559. Earlier research has noted, however, that Kettler occasionally used the title of the master as early as in February 1559. The charter published here is another evidence on Kettlers aspirations. A group of officials of the Teutonic Order in Livonia confirm herewith that they have accepted Gotthard Kettler as their new master on 22 February 1559. Legal ramifications of this charter are not straightforward. The main ratio behind it seems to be the support to Kettler for his mission in Poland, where he was searching for help against Muscovy, and needed to legitimise his negotiating position. Final change in the leadership of the Order still took more time, until the retirement conditions of the old master Fürstenberg were settled.