Which came first, the mule or the mug? Turns out, that iconic copper mug might have been the impetus behind one of America’s favorite cocktails.

The Moscow Mule was famously born of an overabundance of supplies and a need to push product. John G. Martin, head of Heublein & Brothers, had recently purchased Smirnoff distillery and found himself with a surplus of vodka. As Eric Felten reported for The Wall Street Journal back in 2007, Martin’s friend, Jack Morgan, owned Cock ‘n’ Bull bar in Los Angeles. Morgan was also swimming in a product he was pushing: his very own brand of ginger beer. One night, Morgan and Martin were hanging out with one of Morgan’s bartenders, Wes Price, who was also trying to get rid of product. “I just wanted to clean out the basement,” Price would say of creating the Moscow Mule. “I was trying to get rid of a lot of dead stock.” Dead stock meant Smirnoff vodka and ginger beer, of course. Price claims his concoction was first served to actor Broderick Crawford. After that, the drink “caught on like wildfire.”

And what about the copper mug? According to historian of drinks Ted Haigh, Morgan’s girlfriend, Osalene Schmitt, had inherited a business that made copper goods — hence, the mug.

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There are plenty of alternate tales regarding the drink’s humble beginnings, though. A competing narrative was brought to light by the Moscow Copper Co. Their version tells the tale of Sophie Berezinski, an immigrant to the U.S. from Russia in 1941, who arrived on our shores with approximately 2,000 copper mugs in her possession. Her father owned and operated the famed copper company and had a surplus of the mugs that he simply couldn’t sell back home in Russia. Sophie took the products to America in hopes that they’d move quickly, though the mugs didn’t seem to budge. After some time, Sophie’s husband Max threatened to get rid of the mugs if she didn’t make a quick sell. This version has it that Martin and Morgan were at a bar together discussing their business woes and failures to sell their vodka and ginger beer when in walked Sophie, copper mugs and all. After joining their conversation, the three spent hours crafting a drink that could satisfy all of their product-pushing needs.

Believe it or not, another version of the story exists, too. In a 2007 article, author George Sinclair quotes a 1948 edition of the New York Herald Tribune that found that the drink was actually born on the East Coast, in Manhattan, but “stalled” on the West Coast. This version claims that the third person involved in the drink’s birth was Rudolph Kunett, president of the Pierre Smirnoff, Heublein’s vodka division. According to this third version, the three were sipping, snacking, and working toward a brilliant business decision that would benefit the entire trio. The bartender poured them a mingling of vodka and ginger beer with a touch of lemon juice, and a few days later, the Moscow Mule was officially named.

Regardless of the story, it’s generally accepted that Martin was the one responsible for the drink’s takeoff, sparking sales of both his vodka and the copper mug by going to bars and taking Polaroids of bartenders posing with both products. Currently, the Moscow Mule remains one of the most popular drinks in the country, still served up in the same classic, copper mug in which it was created.

Get your own set of these iconic mugs here.