The question is in the title. I think I first heard it in the '80s, though it could have been the '90s, as ‘So-and-So has been named the “Drug Czar” in charge of leading the nation’s fight against drugs.’
Garry Trudeau used to talk about “energy czars” in 70s and 80s Doonesbury. I’m probably wrong, but I’m guessing it started with the energy crisis (Seven Sisters/OPEC) in the early 70s.
It goes back a bit farther than that. According to Time Magazine
White House Czars: A Brief History | Time
" During World War I, Woodrow Wilson appointed financier Bernard Baruch to head the War Industries Board — a position dubbed industry czar (this just one year after the final Russian czar, Nicholas II, was overthrown in the Russian Revolution). Franklin Roosevelt had his own bevy of czars during World War II, overseeing such aspects of the war effort as shipping and synthetic-rubber production. The term was then essentially retired until the presidency of Richard Nixon, who appointed the first drug czar and a well-regarded energy czar, William E. Simon, who helped the country navigate the 1970s oil crisis."
From your link, this is where I first heard it:
The modern drug czarship — perhaps the best-known of the bunch — was created by George H.W. Bush and first filled by William Bennett
FWIW, the czars and czarinas who typically get these informal titles are usually not the heads of government agencies; they’re advisors within the Executive Office of the President whose job generally involves subject-area coordination among several government agencies and sometimes negotiating with Congress.
I first heard it in the 70s in Doonesbury. They aren’t the head of an agency as much as an individual that carries the authority of the President in a selected field. Kind of like those letters of old from the king that told his subjects that the holder of that letter was to be obeyed as if the king gave the order himsellf.
ETA - I didn’t mean to wake a zombie; I have no idea how I stumbled upon this thread.