[2] On 16 April 1863, the 22-year-old Kool married Johanna Francoise Adolphine Diemer in Nijmegen, and the couple had three children, Johannetta, Johan Arthur, and Frederika.

[2] A few years after Diemer died in 1895, Kool married again, this time to Arnoldine Adriana Diederika Pels Rijcken in Arnhem on 29 December 1898, aged 57.

[4] From 28 April 1879 to 8 September 1883, Kool was an officer who was a liberal member of the House of Representatives, where he mainly spoke about military matters, giving long speeches about the defense of his country and the Dutch East Indies, and also about the criminal code, railways, and colonies.

[4] Despite his short mandate, he succeeded in pushing a new proposal about the army reform plans through the parliament, even though the system he advocated was even more costly than the one that the Lower House had previously rejected.

[1] From 1 October 1907 to 1 November 1909, he was in charge of the field army, and as such, he oversaw the construction of the artillery barracks in the Gelderland town of Ede, which were thus renamed after him in 1934: Arthur Koolkazerne [nl].