Johnson is a former Colonel of the United Nations Marine Corps, one of the most decorated officers in the UN military, and the de facto leader of the OPA.
Fred Johnson became famous when he was a Captain with command over three missile frigates. He destroyed a dozen pirate ships and two major bases, causing a drop in piracy in the Belt. Johnson was promoted and given command over the Coalition Marine division responsible for policing the Belt, where he continued to serve with distinction.
When Anderson Station was taken by insurgents, Colonel Johnson led the successful attack to retake the station, killing 173 armed insurgents and over a thousand civilians. This battle earned him fame in the inner planets and the Medal of Freedom, the UN Marines' highest honor, but in the Belt he became known as "The Butcher of Anderson Station".
Unable to cope with his actions, Johnson resigned from the Marine Corps and publicly apologized for his actions. Going underground for years, he started frequenting bars in the Belt, drinking heavily and getting in skirmishes with the OPA, until he encountered Anderson Dawes who recruited him to the OPA.
Four years after his disappearance, Johnson showed up during a Belter revolt against the Coalition on the Pallas colony. He spent a year negotiating between the Coalition and the insurgents, ending the conflict peacefully and improving conditions for workers on the asteroid, and earning Johnson status as a hero in the Belt.
After spending ten years working peacefully to improve the lives of Belters and giving up his Earth citizenship, Johnson has become the OPA's spokesperson and de facto leader, operating out of Tycho Station.