Following the Macharian Crusade, the Lenehenese Imperial Guard was left dangerously undermanned with the ranks barely half of what they should have been, even in peace time. Troops on garrison duty had been withdrawn to halt the advance of the Babylonian forces towards Holy Terra, but in the process had left many outlying cities dangerously exposed to sedition and foreign influence. An example of this was in 1982 when the Governor of Cytheria, a prominent port-city and the hub of most regional shipping, renounced the Imperium and defected to the Panzermeemian Confederacy.

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Panzermeemian Heavy tanks encounter stiff resistance.

Naturally, such an act of heresy could not go unpunished and 7 Imperial regiments were sent to depose the governor and bring the rebellious city to heel. However, the Panzermeemian Confederacy refused to let such a rich provence slip away and a taskforce of their own was dispatched. Initially the Lenehenese re-captured the city, executing the Governor and imposing Martial Law until it had calmed but soon reports came in that a large enemy force was making it's way for the city. The Lenehenese dug in deeply but the Panzermeemian attack was spearheaded by heavy tanks and multiple waves of infantry. Heavy casualties were taken, but the city was wrested from Lenehenese hands and their army was shattered, the entire 9th Cadian Armoured had been destroyed and the remaining infantry was scattered and isolated. Vigourous sweeps of the surrounding area hunted down these rogue groups and one by one they were destroyed, all except for the 18th Harakoni Warhawks. Seeing the devastation of their army and knowing they could never survive a direct confrontation with better equipped Panzermeemians, they retreated back into the jungles where they prepared for a protracted guerrilla war.
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A Harakoni platoon ambushes an isolated convoy.

Eventually they were forced to give battle and the regiment was splintered. Scattered remnants of Lenehenese forces mounted sporadic guerrilla attacks on vulnerable targets in hope of eventual reinforcements until they were withdrawn in 1986.

The city had been captured but at a terrible price for the Panzermeemians, and rumours say that the Lenehenese are biding their time, waiting for a chance to reclaim their lost possession.