Tresoar 1074R, which is a copy of the only Frisian incunabulum that is usually referred to as Freeska Landriucht, contains several handwritten notes from the 16th century. The notes, which are in Latin as well as in the vernacular, are written on a misprinted bifolium preceding the book’s main text. The notes make abundantly clear that in the 16th century the incunabulum was part of the library of the East Frisian castle at Oldersum; what is more, it is the sole recorded survivor of this large book collection, since the library seems to have been completely scattered and destroyed in the decades following the death, in early 1589, of the last male descendant of the Oldersum chieftain dynasty: Hero ii von Oldersum. Caspar Möller, a legal officer in Oldersum, handed it out to Henricus Reiningius of Coevorden, a notary public, on 20 April 1589, which is the very day after a (surviving) inventory of the Oldersum book collection was made. Although the Freeska Landriucht is not mentioned specifically in the inventory, reference to it may still have been made by Johan van Westerwolt (who inventoried the library) with the words: Ein olt geschrieben Landrecht.
BremmerRolf H.Jr, 'Constantijn Huyghens’ Interest in Old Germanic Studies: A Lost Book from his Library Retrieved', in Jan F. van Dijkhuizen(ed), Living in Posterity: Essays in Honour of Bart Westerweel, (Verloren, Hilversum2004b) 39-45.
Gretje Schreiber(ed), Ostfriesische Beamtenschaft. Die Amtsträger der landesherrlichen landesständischen und städtischen Verwaltungen der Grafschaft bzw. des Fürstentums Ostfriesland von 1464 bis 1744, (Upstalsboom-Gesellschaft, Aurich2007) 5 Vols..
van ThienenGerard, 'A Date for the Freeska Landriucht Press (1484–7) from Paper Evidence. With a Note on the Codex Roorda', in Martin Davies(ed), Incunabula: Studies in Fifteenth-Century Printed Books Presented to Lotte Hellinga, (British Library, London1999) 141-167.
Popkema (2003) is a short introduction to a digital facsimile of one of the Leeuwarden copies of the Freeska Landriucht (A iii 31). Janssen (2015) likewise offers a facsimile as well an introduction focusing primarily on the Utrecht copy (J oct 1112).
Popkema (2016) offers a full transcription including gloss A which Engels was unable to read in 1977 (aside from the word ‘arfnisse’; see Engels (1977: 19)). uv lighting and extremely high definition photography (by Anke van der Schaaf) made it possible to transcribe much of gloss A and even fragments of gloss E which Engels seems to have overlooked completely. The five different hands that were identified are indicated by the letters A–E.
In Popkema (2016) Hero ab oldersum was erroneously equated with Hero i von Oldersum; Hero i was Hero ii’s grandfather who died in 1559.
The wall was not built until1579one year after Boiocko’s death. As for the division of books: we do not know how (or even if) Hero i organized the division of his archive and library. At any rate there were two separate libraries in Castle Oldersum in the last quarter of the 16th century: Boiocko’s in the southern and Hero ii’s in the northern part see Kannegieter (1987: 31 and 36 respectively). Court logs (over the years 1527–1587) were kept outside of the castle in the ‘Richthaus’ which was on the castle grounds see Kannegieter (1987: 36 and 32 [no. 6 on the map]).