This is the publication of the grant issued in 1519 by the Voivode of Vilnius and the Chancellor of the State Mikalojus Radvila (Mikołaj Radziwiłł) in favour of landowner Jan Sławski. It is a document written on a parchment in a manner akin to the humanist minuscule. The parchment has a red wax seal of Mikalojus Radvila attached to it. The published document is accompanied by the text aimed at disclosing and relating the history of the issuance and existence of this document. The main reasons for drawing up such document was the model of Mikalojus Radvila’s rule in Podlachia. When in 1509 the sovereign Žygimantas Senasis (Sigismund I the Old) conceded the domains in Goniądz and Rajgród to the said nobleman and in 1517 also granted the immunity, Radvila employed several interrelated methods to establish his power in the territory. Alongside the castle another important manifestation of such power was subordinate noblemen who eventually would become local officers and form a part of the organization of the lord’s court. The recipient of the published document – landowner JJan Sławski – also found himself in a similar network of the lord’s power. The drawn up document was aimed at establishing and recording the relations between the lord and the representative of the petty nobility. The medium of Mikalojus Radvila’s court (and, we can guess, also the chancellery) was favourable for such task. The Latin text of the grant was written on the parchment by Mikalojus Husovianas (Mikołaj Hussowczyk) who served as M. Radila’s clerk (lat. notarius). The newly discovered data make it necessary to adjust the knowledge of the latter humanist’s biography and activities in the period in question. The document defined the subordination based relations between M. Radvila and the nobleman. The said relations were confirmed by means of granting (verifying) the Mikitin domain and newly allocating a neighbouring domain. Such grant and the domains in Jan Sławski disposition ensured his service to M. Radvila which first and foremost meant military service. The established relations can be interpreted in the context of feudal relations (relationship between lord and vassal, fief, etc.). In this case the published document becomes a rare source shedding light on such relationship “from within”. Situations established (or recorded) by the document, the fate of the Radvila family’s rule in Podlachia and that of certain social processes in the state are closely interrelated and mutually supplementary. The death of the Voivode of Vilnius and the Chancellor of the State Mikalojus Radvila in 1522 was followed by unrests in his domains – the discontent was mostly expressed by subordinate noblemen. Jan Sławski was among them. Several court litigations resulted in the landowner being issued with a new privilege for Mikitin domain in 1528. In 1529 together with a group of other noblemen he was freed from the Radvila “yoke”. These events occurred in the same year when Žygimantas Senasis issued the land privilege which provided for the restrictions regarding the formation of tiered subordination. In 1522, based on the Sovereign’s order, Slavskis was expected to return the document to the Radvila family. Actually, we cannot tell for sure if he did what he was ordered to do. Later, it was owned by Bona Sforza and after 1569 became a part of the archives of the Crown Treasury in Wawel. In 1765 the archives were relocated to Warsaw and following the occupation of the city, were moved to Russia. In 1799, after the Prussian authorities explicitly declared their wish to obtain archival materials pertaining to the territories under their control, the document most probably was stored in Białystok. In 1854 via Grodno the grant together with other documents reached the Archives of the Ancient Acts established in Vilnius, which later in its own turn handed the parchment over to Vilnius Public Library.