Chris Stapleton’s debut album arrived at the right moment. Country music was awash in charged-up tunes about bikinis and tailgating, and Stapleton’s rawhide Kentucky voice immediately evoked earlier eras. He became one of Nashville’s most unlikely success stories. Stapleton (born in Lexington in 1978) was already an established songwriter for Kenny Chesney, George Strait, and others when he released his 2015 debut, Traveller. He was in his mid-thirties, with unfashionably long hair and an expansive beard (the best in Nashville since William Lee Golden threw away his razor). His mixture of Southern rock, classic country, and blues didn’t sound like anything else on the radio, and the songs were dark explorations of hard times and boozy unhappiness: “I drink because I’m lonesome, and I’m lonesome ’cause I drink,” he sang in “Whiskey and You.” Traveller grew through word-of-mouth enthusiasm, one person saying, “You’ve got to hear this guy” to friends who told their friends. Stapleton thought selling 75,000 albums would count as a triumph. Then, in November 2015, he won three Country Music Association awards, including the biggest prize, Album of the Year. Traveller went to No. 1 on the Country charts and sold nearly 3 million copies. Grammy awards, Saturday Night Live, and an appearance in Game of Thrones followed. The stark clarity of Stapleton’s songwriting, his carefully modulated baritone, and Dave Cobb’s guitars-forward production brought together mainstream country fans and alt-country hipsters, two groups that rarely meet. Stapleton, who records and performs with his wife, singer Morgane Stapleton, is refreshingly undogmatic for a traditionalist; he’s recorded with Justin Timberlake and with P!nk, and Adele and Kelly Clarkson have cut songs that he wrote. There’s little risk that he’ll run dry of material; by Stapleton’s estimate, he’s written more than 1,000 songs.