For the next two centuries, people had to make do with this ambiguity, as they looked for a good way to signify a plural “you.”
They tried, for example, putting a plural “s” on “you,” making it “yous” or “youse,” both odd looking. Others tried adding a word after “you” to indicate plural: “you people,” “you folks” and “you ones,” or more colloquially “you-uns,” abbreviated “yinz.” Some added a word specifying the audience, like “you ladies.” None of these options had much widespread success, except for the special case of “you all,” also “y’all.”
Meanwhile, while no candidate was attractive enough to step into the shoes of “thou,” a word was born that would twist and turn on its way to success. It came from the terrifying near-success and utter defeat of the Gunpowder Plot, a scheme to explode 36 barrels of gunpowder under the House of Lords in London on Nov. 5, 1605, when Lords and Commons and bishops and other nobility and royalty gathered in that one room for the annual opening of Parliament. The arch-villain who nearly succeeded in blowing to bits hundreds of leading officials of King James’ Protestant government so that Catholics could take their place was an English Catholic gentleman and soldier named Guy Fawkes. He was in the basement under the House of Lords, ready to light the fuses, when a search party caught him just in time.
Soon his name was on everyone’s lips, as he was interrogated, tortured, tried, convicted and executed before the end of January 1606. But that wasn’t enough for the relieved legislators, who realized that they would likely have been killed if the Gunpowder Plot had succeeded.
That led to the pivotal moment in the history of “guy”: Parliament approved a “Fifth of November Act,” that is, “An act for publick thanksgiving to Almighty God every year on the fifth day of November.” The new holiday would feature special religious services during the day and bonfires at night, lighting fires to mock the man who hadn’t succeeded.
In the fires they burned effigies of the Pope, Guy Fawkes and other archenemies of the moment. They referred to the effigies of Fawkes as “guys.” And then some people began to use “guys” to refer to actual people: men of the lowest and most depraved kind. This was early in the 18th century, more than 200 years ago.