Following World War II, with a booming economy, cheap gas, and a growing highway system, Americans were driving more miles every year, and buying more cars. In the 1950s, the iconic Cadillac tail fin became a symbol of prosperity, and it continued to grow until, in 1959, it was over a foot high. The ’60s would usher in the muscle cars. Inspired by the success of the 1965 Ford Mustang, we soon had GM’s powerful GTO and plenty more like it. Here is a sampling of the sumptuous and seductive mid-century automotive ads that helped sell those cars, selected from our new special collector’s edition, American Cars: 1940s, ’50s & ’60s.