.J. c. Vergouwen's work, Het Rechtsleven der T'oba-Bataks, here presented in an English translation, was published in the autumn of 1933, a few weeks before the author's death at the early age of 44 from tuberculosis, from which he had suffered since 1930. During the time he spent in a sanatorium in Davos and later in the Netherlands, he began and completed his monograph on the customary law of the Toba-Batak. His book immediately became one of the outstanding works of Dutch scholarship on Indonesian customary law (Adat law). Jacob Cornelis Vergouwen began his career as an administrative officer in South Borneo (now Kalimantan) in 1913, after a brief prac- tical training. In 1921 he was given the opportunity for further study at the University of Leiden where a five-year scientific training for a career as an administrative officer in the Dutch East Indies had just been instituted. On obtaining his Master's degree, he was appointed to the Tapanuli Residency, from of old, the homeland of the Toba, Mandailing, Angkola, and Dairi or Pakpak Batak. As a young official, Vergouwen had already evinced great interest in the laws and customs of the Dayak people in Borneo.
His studies at the University brought him into close contact with the founder of the science of Indonesian Adat law, Professor Cornelis van Vollenhoven, one of the greatest Dutch jurists of this century.