At the beginning of Operation UNION HOLD, the Star League invasion of the Outworlds Alliance in 2581, Clay Strombergs was a Lieutenant General in the Star League Defense Force, and was the Commanding Officer of a brigade within V Corps, one of two SLDF corps assigned to the conquest of the Alliance.
During the first wave of attacks on the Alliance, Strombergs was ordered to conquer the mining world of Weisau; the first of his forces landed on the 2nd of August 2581, seizing transport hubs and spaceports. Strombergs then began a two-part strategy to conquer the world; first, he used his troops to cut off the supplies arriving from off-world that the planet relied on. Then, he promised amnesty to any who turned in their weapons. This was followed up by the offer of lucrative contracts with the Star League in exchange for executive Star League oversight to the individual mining concerns.
While this strategy made some headway, the planet soon descended into chaos as those miners determined to resist attacked both Strombergs' forces and those they viewed as collaborators, taking opportunities to capture resources wherever possible. Strombergs finally resorted to launching major offensives against the largest of the mining holdouts, winning battles of attrition that his troops could sustain but which the miners could not. This ultimately pacified the planet, but led to Strombergs' forces requiring several weeks to repair all of the equipment damage inflicted by the inhabitants.
The commander of the Outworlds Alliance task force, General Amos Forlough was unimpressed with V Corps in general, and the length of time it took Strombergs to capture Weisau didn't help; as a result, Forlough relegated V Corps to a support role in 2582.
Historical: Reunification War indicates in the entry on the battle for Weisau that Strombergs was in charge of the forces attacking the planet, and that he commanded three regiments of troops - a brigade. However, it doesn't specify which brigade in the text. The deployment table listed on p. 141 of Historical: Reunification War shows two brigades as being deployed to Weisau in 2581 - the 43rd Brigade and the 45th Brigade - rather than just the one brigade. It is therefore not currently known whether Strombergs commanded the 43rd or the 45th and which annexed Weisau.
- Historical: Reunification War, p. 113-114, "Weisau"
- Historical: Reunification War, p. 119, "Haynesville"