Karl Kilbom was born in 1885 in the Uppland region. His father was a smith who, when he tried to form a union, recieved threats from his employer and told Karl to stay out of politics. When he eventually moved away from his father (the mother passed away when he was young) he found a job
as a sailor before eventually being drafted and serving at the ship HMS Svea in 1907. After his military service he moved to Göteborg, where he met big names in the left movement. Soon enough Kilbom started doing journalistic work for various political newspapers and became a big name in the far left movement of Sweden. Despite various splits and inner conflicts Kilbom has managed to stay close to power.