The graph above plots mentions in books of the name "Ivan Illich" between the years 1960 and 2008, as calculated by Google's newly released Book Ngram Viewer. It's a fun service to play with. We read about this today in the NYTimes.
No surprises, here. As would be expected, mentions of Illich take off in the late 1960s as he starts publishing his own books and the mentions drop off as he moves on to new and more challenging topics.
Interestingly, though, running the same search across the years 1800 to 2000 reveals a small rise in frequency around the turn of the last century. (see below) Zoom in and Google reveals that these mentions most likely refer to a certain Ivan Illich Petrunkevich, identified in a 1900 journal as "a veteran leader of the Russian liberals" who were then urging the Czar to adopt reforms. He ought to have listened.