Like his elder brother Jaime, he was trained to enter the Warrior caste despite being a freebirth and was assigned to the second-line Choyer Garrison Cluster on Circe where he handed a sound defeat to Clan Snow Raven's Fourteenth Raven Battle Cluster in a Trial of Possession over the Beta Three Mining Complex. For his performance on Circe he was allowed to enter a Trial of Position for a frontline unit, namely Natasha Kerensky's Trinary of the elite 328th Assault Cluster, where he served under Star Commander Katya, a Trueborn from the same sibko that produced Natasha Kerensky. He fought exceptionally well against Clan Jade Falcon forces on Eden in 3002 and achieved the rank of Star Commander the following year.
He was offered to become second-in-command to his brother Jaime in Wolf's Dragoons and went with them into the Inner Sphere in 3004. Joshua Wolf had a talent for administrative duties and was deeply involved in contract negotiations and liaison duties with employers of the mercenary unit.
At some indeterminate point during the Dragoons' mission (circumstantial evidence suggests during their contract with the Capellan Confederation) Joshua Wolf and Natasha Kerensky, who had also joined the Dragoons, became lovers.
Major Joshua Wolf was detained by the Dragoons' current employer, Duke Anton Marik, over contract disputes together with 27 other staff members in early 3015. When brought before the Duke alone on 15 March, he was shot by Vesar Kristofur "in a struggle with his guards", although it remains unclear whether Kristofur shot him in self defense or deliberately killed him with the intention of pitting Wolf's Dragoons against their employer. Subsequently, the Dragoons attacked Anton Marik's HQ on New Delos and a furious Natasha Kerensky razed Duke Anton Marik's stronghold, killing the Duke. She afterwards emerged as the self-styled "Black Widow".
- Decades after his death, Jaime Wolf would name his youngest child Joshua in his brother's honor.