Johannes Lodewijk Pretorius was born on 24 May 1872 and was the sun of the late commandant Henning Pretorius.
A few years prior to the Jameson raid he was working as a civil sevant in the office of the Commandand-General
and start his military career as a private and later officer in the Vrijwilliger cavillary corps at Pretoria.
In Januray 1896 he was appointed as a 2nd Lieutenant for the State artillary and was present at the war against Mpefoe.
On 28 September 1899 he left for Zandspruit in charge of the Third battery and later under generals Lukas Meyer and Louis Botha was at the battle of Talana Hill near Dundee, Modderspruit, Colenso, Platrand and Peters Hill.
When the commando’s was defeated in Natal he departed with the Commandant-general and a section Veld artillary to the Free State and was present at all the battles between Bloemfontein, Johannesburg and Pretoria.
He was also at the battles of Donkerhoek(Diamond hill) and Dalmanutha.
During the war the Commandant-general promoted him to the rank of Major
During December 1901 he was caught and sent to St Helena as a prisioner of war.