Def Leppard England Nov 1977 1977 Def Leppard is formed Joe Elliot joins "Atomic Mass", which consisted of Rick Savage, Pete Willis and Tony Kennedy. 1982 Phil In, Pete out of Def Leppard In 1982, Pete Willis was fired from Def Leppard during the recording of "Pyromania". Phil Collen joins Def Leppard 1 day after Pete Willis departure. 1983 Pyromania Pyromania is released 1991.01.08 Death Of Steve Clark Steve Clark was found dead from alochol abuse 2005.05.17 Rock Of Ages Def Leppard releases "Rock Of Ages" their 1st double-Cd collection in the USA