Conversation so far:
How did Paul Anka's success begin?
The song Diana brought Paul Anka stardom as it rocketed to No. 1 on the Canadian and US music charts.
What did people think of Paul Anka's singing?
Paul Anka's singing made him one of the biggest teen idols of the time.
Did Paul Anka collaborate with anyone?
Paul Anka's talent included the theme for The Tonight Show Starring Johnny Carson
What was the name of the theme Paul Anka wrote for The Tonight Show Starring Johnny Carson?
Johnny's Theme is an instrumental jazz song played as the opening theme of The Tonight Show Starring Johnny Carson from the show's inception in 1962

Question: what is a notable fact about his early career?
Self-contained rewrite: What is a notable fact about Paul Anka's early career?