Nevada’s first governor, Henry Bladsel, wasn’t a fan of gambling. He called it “an intolerable and inexcusable vice” after taking office in 1864, and he convinced the legislature to strengthen penalties against gambling.
That didn’t stop Nevadans from gambling, and in 1869 the legislature passed a law legalizing gambling. Over Bladsel’s veto. The rest is quite literally history.
You can read the entire story of Nevada gambling in Roll the Bones: The History of Gambling.