"The earliest documented performance with an electrically amplified guitar was in 1932," according to Wikipedia. The electric guitar was used by Hawaiian Style musicians. George Barnes reportedly recorded the first 2 songs with the electric guitar in 1938.
Now, Rock 'N' Roll without the electric guitar, is a folk song; slap a banjo on your knee and rock with a toothless hockey player on the harmonica. Howstuffworks calls it the best thing since the incandescent light bulb....
]]>