The origin of sliders dates back to J. Walter Anderson's invention of a hamburger patty between buns in the early 1900s. Despite debates on the true creator of the contemporary hamburger, Anderson's innovation led to the opening of the first burger place in 1916, where burgers were sold for five cents apiece. These burgers came to be known as sliders, specifically cooked with raw onions. Originating in Wichita, Kansas, sliders gained popularity due to the city's demographic mix of laborers in need of quick, affordable, and satisfying meals during the early 1900s.
White Castle has its own take on fast food hamburgers. For starters, the patties are square, with five holes in each patty. And they’re small, too –- two-and-a-half inch sliders. Just big enough to fit into the palm of your hand. And since they’re steamed on a bed of onions, everything is infused with this very specific onion-esque flavor.
Today, White Castles can be hard to find, depending on where you live. But KCUR's Mackenzie Martin, a producer at A People's History of Kansas City, says that it’s time to stop thinking of White Castle as a semi-obscure cultural punchline, because over a century ago, White Castle invented something that became so important and all-encompassing that, today, it touches pretty much every person in America. Sometimes several times a day. Something that, in other countries, has almost come to define American culture: it has a strong claim to being the first fast-food restaurant.
The White Castle System of Eating Houses