Let's see... https://books.google.com/ngrams/graph?content=history+never+repeats+itself%2C+history+repeats+itself&year_start=1800&year_end=2000&corpus=15&smoot

Let's see... https://books.google.com/ngrams/graph?content=history+never+repeats+itself%2C+history+repeats+itself&year_start=1800&year_end=2000&corpus=15&smoothing=3 https://books.google.com/ngrams/graph?content=history+never+... Looks like "history repeats itself" is clearly the more frequent formulation.