We'll Knock The Heligo—Into Heligo—Out Of Heligoland! is a World War I song written by John J. O'Brian and composed by Theodore Morse. The song was first published in 1917 by Leo Feist Inc., in New York, NY. The sheet music cover depicts a terrified Kaiser standing on a cliff with a city below and United States soldiers rushing toward him.
The sheet music can be found at the Pritzker Military Museum & Library.