There were also efforts to explain scientifically what was happening.
An article in the New York Times in 1921 theorized space dust was responsible.
|New York Times, November 20, 1921|
Seems that bouts of warming and cooling have been going on as long as the Earth's been around.
The difference between now and in the past is that in the past, scientific theory was presented as theory, and wasn't designed or exploited as an excuse to control or manipulate people or whole populations for political purposes as it is now.