This diorama is a scene from the 1980 film “The Empire Strikes Back”, where the Imperial forces attack the Rebel Alliance’s Echo Base on the ice planet Hoth in the Anoat sector.
The Imperial force consisted of primarily AT-AT Walkers (All Terrain Armored Transport) commanded by General Maximilian Veers.
Note:
Although this diorama is my own fictional account of a Star Wars event, all other information provided are Star Wars canon that can be verified by Wookieepedia (https://starwars.fandom.com/wiki/Category:Creatures_of_Hoth).