Kubrick's long shadow looms large over especially the opening of Lucas's space epic.
Stanley Kubrick's 2001: A Space Odyssey was a tremendous influence on Lucas, both for the style and tone of THX 1138 as well as for Star Wars, where it provided ideas for shots, but also the impetus to create realistic looking, kitbashed models.
Lucas went to see Forbidden Planet for his 12th birthday, and never looked back. The equivalent to what Star Wars would become for later generations, it was indeed an Amazing! Never Before Seen! science fiction extravaganza, and it left its DNA all over Star Wars.
Not long out of USC, Coppola's production company American Zoetrope, started its life with Lucas's first feature film, THX 1138. The art house precursor of Star Wars.
WWII was an enormous influence on all kids of the 50s and 60s, and Lucas was no exception. From the general good vs evil nature of the conflict to the specifics of war epics like The Guns of Navarone and air-heroics of The Dam Busters and 633 Squadron, it seems entirely possible that Star Wars would never have existed if not for the war.