The 4th Task Force was created at the onset of the Extremis Campaign at the end of M41. In a time of great strife in the fringes of the Segmentum Pacificus, where the scattered and beaten forces of Chaos fled into the various Imperial worlds there. Some of these forces descended upon the worlds of the Segmentum Pacificus with overt wrath, pillaging and destroying all that they could. While others landed quietly and began to sow the seeds of Chaos and incite rebellion among the populace. Whatever the method, the widespread panic and rebellion needed to be stopped. It was for this purpose that a massive military force was created. Comprising of nearly one billion soldiers and millions of machines, the 4th Task Force was to spread through the Segmentum and despatch any who stood before them. The Task Force was drawn from whatever Regiments were available nearby, including Cadians, Vostroyans, the Steel Legion, and the Death Korps of Krieg.
One small fraction of this massive military machine was:
4th Task Force, 3rd Army, 2nd Corps, 3rd Division, 2nd Brigade, 14th Regiment. The 14th Cadian Mechanized Infantry Regiment is led by Col. Manfred Eisenberg . Arrayed with a large number of armored vehicles as well as with many heavy weapons the goal of 14th Regiment was to bring overwhelming firepower to any fight. For Heavy Armor support the commander has the support of the 125th Cadian Armored Division. Contingents of the Imperial Navy's 357th Close Support and Transport Wing were also on call for the regiment, allowing them to conduct airborne raids on enemy strongpoints.
Over the next 15 years the forces of Chaos were slowly polished away, and as the size of the threat diminished, so to did the size of the 4th Task Force. Other enemies in other Segmentums were arising and the Imperium had greater needs elsewhere. Each of the 10 Army Groups of the Task force were diverted to new theatres of operation after the 10th year of the Campaign.
At the final Victory on the world of Tarnarsis Majoris only the 3rd and 7th Army Groups remained part of the original 4th Task Force. Col. Eisenberg had since been promoted to Major General and had command of the entire 3rd division. The 14th Mechanised is still a Cadian regiement, but has picked up some leftovers from Krieg, Armageddon, and Vostroya. The Victory would be short lived, and within weeks of the conclusion of the campaign a new foe arose elsewhere in the galaxy, there would be no rest for the 4th.