Adriaen Valerius, like Guillaume de Machaut a poet as much as a composer, has a certain importance in the musical history of the Netherlands, principally for his collection Nederlandtsche gedenck-clanck of poems and songs dealing with peasant and burgher life and with the Dutch War of Independence against Spain. The collection included the songs Wilhelmus (after the great Dutch leader of the revolt against Spain William of Nassau / Wilhelmus van Nassouwe, aka William of Orange), which later became the Duth national anthem, and Wilt Heden Nu Treden, which was transported to the Americas by the Dutch settlers of New Amsterdam (later New York) and became well-known there as the song of Thanksgiving We Gather Together, as well as in Germany, in its German translation Wir treten zum Beten or Altniederländisches Dankgebet, where it became “became a potent symbol of the ‘Throne and Altar’ alliance of German civil religion until 1918.” (Wikipedia).
Willem Mengelberg had performed both pieces with the Concertegouw Orchestra a number of times since the end of the 19th Century, the anthem in his own arrangement. He recorded both (the Thanksgiving prayer in a new arrangement by Johan Wagenaar) in December 1938, on a Telefunken 78 rpm, A 2899 (10”) or NK 1965 (12”). It is those recordings that were reissued by Teldec on Willem Mengelberg Concertgebouw Orchestra: Niederländische Komponisten. Works of Valerius/Wagenaar, Dopper, Röntgen, Hendrik Andriessen, Rudolf Mengelberg, Wagenaar, Marnix von St. Aldegonde/Mengelberg. Teldec 243 723-2 (1988).