Immigrant Song was released by Led Zeppelin in 1970 as the opening track on Led Zeppelin III, with Robert Plant delivering its famous wordless opening cry. The song drew on Norse mythology and Viking imagery, giving the scream a warrior-like charge that matched its driving guitar riff. Decades later, its use in the Thor: Ragnarok trailer and film in 2017 introduced it to a new audience, and short clips of the opening scream began circulating as a meme sound for dramatic, heroic and exaggerated moments online.