Battle of Gormen
this was one of many skirmishes which occurred during the Galactic Civil War, in the wake of the Battle of Hoth. The Alliance's forces had nearly won the battle, but the Empire had been holding back a group of AT-AT walkers until absolutely necessary. As the AT-ATs emerged from the smoke and haze, the civilian troops fled in terror and the Alliance forces simply surrendered, knowing that it was impossible to outrun the walkers.