There are many claims of being the first to invent the ice cream sundae, all of which share a similar story. In the late 1800s, sodas were mixed by hand using syrups, and one day, someone used those syrups to top ice cream. Of course, each version of the story has a connection to serving it on Sunday, and thus the Sundae was born.
The oldest claim seems to be from soda shop owner Ed Berners of Two Rivers, Wisconsin, who created his first Ice Cream Sunday after a customer requested it in 1881. Similarly, Chester Platt, the owner of an Ithaca, New York, drugstore fountain shop, said he created the dish in 1883 for a reverend on a Sunday.