Recently the Peace Palace Library received a gift from the children of D.J.H.N. den Beer Poortugael (Herman den Beer Poortugael). The gift, a book titled: “De bijdrage van Nederland aan de codificatie van het moderne humanitaire recht (1800-1914)” is an adaptation of the dissertation written by Herman den Beer Poortugael, former head of the military police of the Netherlands. Unfortunately, just before he had to defend his thesis, he died at the age of 82. He worked on the dissertation for fifteen years.
In his dissertation Herman Den Beer Poortugael focused on the role of the Netherlands regarding the codification of humanitarian law and the law of war during the period of the nineteenth century until the First World War. He also paid attention to the participation of his great-uncle J.C.C. den Beer Poortugael (1832-1913) concerning the codification of humanitarian law during this period.
J.C.C. den Beer Poortugael initially was not a jurist. He was trained as an infantry officer at the Royal Military Academy of the Netherlands. J.C.C. den Beer Poortugael, the great-uncle of the author, became director of the training department of the military staff of the Netherlands. During that period J.C.C. den Beer taught politics of war at the training department (military school). Amongst other things the discipline 'politics of war' covered public international law and the law of war. For the sake of teaching this discipline, J.C.C. den Beer Poortugael wrote a manual on the law of war in 1872, which was called: “Het oorlogsrecht”. Writing this manual made him a distinguished authority in the field of humanitarian law. 
In the following years J.C.C. den Beer also became intensely involved with government issues as a statesman after becoming a Minister of War and later as a member of the Council of State of the Netherlands. Besides these positions, J.C.C. den Beer contributed to the final text of the Oxford Manual of 1880, a manual on the laws of war on land as a member of the Dutch delegation. He also was a member of the Dutch delegation to the Hague Peace Conventions of 1899 and 1907 and the Conference of Geneva in 1906. The achievements of J.C.C. den Beer Poortugael have shown that he was a true humanitarian throughout his career.
The author was of the opinion that the peace conferences in The Hague in 1899 and 1907 were essential to the further development of international humanitarian law. The pioneering codifications that came into existence during this period had an influence on all later codifications of humanitarian law. The Netherlands contributed to this endeavor not only by its diplomatic and foreign policy to pursue the general interests of the international community but also through contributions made by Dutch jurists to the codification of humanitarian law. The progressive suggestion of C. van Vollenhoven to create an international police force in 1910 also serves as an example of Dutch efforts towards the codification and development of international law.
 D.J.H.N. den Beer Poortugael , “De Bijdrage van Nederland aan de codificatie van het moderne humanitaire recht (1800-1914)” Thieme MediaCenter: Nijmegen, 2009, p. 17.
 Ibid., p. 108.
 Ibid., p. 209.