Original: The team , a member of the National Hockey League ( NHL ) , was relocated to Calgary , Alberta , Canada for the start of the 1980 -- 81 NHL season and were re-named the Calgary Flames , leaving Atlanta without an NHL team , before the Thrashers were formed 19 years later .
Simplified: The team was moved to Calgary , Alberta , Canada for the start of the 1980 -- 81 NHL season and were renamed the Calgary Flames .