Liverpool is one of the most important cities in English history and has had a huge impact throughout the world, particularly in the United States. Rock and rollers of a certain age remember that a group of four mop-headed young men formed a music combo here, named the group the Beatles, and proceeded to change the world. But Liverpool played a huge role in England's domination of world shipping and was strategic in war as far back as the U.S. Civil War in the 1860s.