The Cheesy Popularity Spike of 1880

Take a good, long look at this folks:


That’s a Google graph for usage of the word “cheesy” in digitised books over time. I’ve already forgotten why exactly I needed this data in the first place, but I’m glad I’ve got it now. Maybe there’s a perfectly normal explanation for why the 1870s were such an extraordinarily good decade for the word cheesy, but I like to image it’s solely down to a sudden cultural saturation of the phrase “It ain’t easy bein’ cheesy”, which has since been forgotten about by all but the most crusty, over-ripe philologists.

Almost as puzzling is the sudden drop-off that occurs around 1950 – You’d think the rise of fast food chains would have made the word practically de rigueur, but apparently not. The improved fortunes of cheesy in the 1990s are understandable, but the Matterhorn-esque profile in the centre board attests to a more than ten-fold increase in cheesy’s lexical real estate between 1860 and 1880. It lacks rind or reason.

Can anyone offer an explanation for this?