The origin of tapas is attributed to various Spanish monarchs over the centuries, whether to mitigate the effects of alcohol or keep flies or sand out of their drinks by putting a bit of bread with a slice of sausage or cheese or whatever on top.
Back in the 16th century, Cervantes wrote a story called Rinconete y Cortadillo, in which two characters sell little snacks on street corners for men to take to the taverns, as it was prohibited to sell food and alcohol together in bars at that time – and that’s how many believe it all began.