Nashville in 1993 wasn't the glittering weekend destination it is in the present day, with its gleaming new high rises reaching skyward and cranes dotting the sky in every direction. Though downtown was buttoned-up and business-like during the day, it could be empty and menacing after nightfall. Meanwhile, there was a veritable gold rush happening right up the road on Music Row.


That's the Nashville Angelo Petraglia saw upon his arrival. The New York native had made the rounds in Boston's rock scene, including scoring a minor hit with the band Face to Face, before shifting his attention southward. But he wasn't necessarily interested in in discovering rock & roll when he got to town – his quest was, like so many Nashville transplants, to become a country songwriter. What he ended up doing instead was helping chart a course for the new sound of Nashville through his production and songwriting work with Kings of Leon, Taylor Swift, Patty Griffin, Carrie Underwood and many others.


Angelo had originally found country music through the back door, obsessing over the Rolling Stones' heady mix of twang and scuzz on Sticky Fingers and learning about the British rockers' productive (if drug-addled) friendship with country-rock pioneer Gram Parsons. The Band's epochal Music from Big Pink, with its groove-heavy cover of the country murder ballad "Long Black Veil," was another important touchstone, mixing a rock sensibility with more traditional song forms.


Living in a hotel room near downtown for $400 a month (try getting that in Nashville these days), Angelo hit the ground running and began taking meetings. Rock & roll wasn't a huge presence in Nashville at the time, but Garth Brooks and the first wave of the country boom were injecting some of its rowdy energy into the country space. Angelo also discovered that many of the architects who had originally built the institutions of Music Row were still active players in the business – it was actually possible to have a beer with songwriting legend like Harlan Howard in the middle of the week and attempt to siphon off a little of his expertise. When creative types from the coasts realized there were embarrassing amounts of money to be made in country music, the flood began. Bob McDill wrote "Gone Country" about the trend, which – if we're being fair – probably didn't exclude Angelo.


Music City interloper or not, Angelo had a good run in the burgeoning alt-country scene not long after he arrived. Singer-songwriter Kim Richey included several compositions co-written with Angelo on her self-titled Mercury Records debut and her acclaimed 1997 follow-up album Bitter Sweet was his first time to sit in the producer's chair, having assembled the band from Nashville session players and a few of his Boston pals. Additionally, Angelo straddled yet-to-widen country and Americana gap, co-writing "One Big Love" for Patty Griffin's Flaming Red and co-writing the Grammy-nominated Trisha Yearwood hit "Believe Me Baby (I Lied)" with Richey and Larry Gottlieb.


The next, considerably more intense run of success put the unassuming Angelo at the heart of an American rock & roll revival as producer and writing partner with back-to-basics Tennessee band Kings of Leon. Originally pitched as a country duo between brothers Caleb and Nathan Followill, their stylistic transition to full band with their other brother Jared and cousin Matthew was nurtured by Angelo. Moreover, he gave the sheltered Pentecostal siblings a much-needed rock & roll 101, introducing them to the Clash and the Rolling Stones. It was prescient timing: a wave of bands like the Strokes, the White Stripes and their ilk was reclaiming rock & roll from the sound of post-grunge as KoL arrived. All told, Kings of Leon retained Angelo as their producer for six total albums, from the boogie and Southern rock of early releases Youth and Young Manhood and Aha Shake Heartbreak that conquered Europe to 2013's Mechanical Bull. In between, they experienced a massive commercial breakthrough with Only by the Night that briefly made them the biggest band on the planet and earned Angelo a Record of the Year Grammy for the single "Use Somebody." Their partnership ran its natural course, but it's hard not to speculate whether it would ever happen the same way again.


What's remarkable is how, for someone who came to Nashville to write country songs, Angelo's work has refused to stick neatly inside one musical genre. In addition to the more recognizably country songs he's written with Taylor Swift or Carrie Underwood, he's also collaborated with a range of performers like British rockers Kaiser Chiefs, singer-songwriter Lissie and soulful Peter Wolf of J. Geils Band. Recently, he even scored his first country top 10 as producer with Tucker Beathard's gritty, guitar-driven "Rock On." There's never a particular formula or set of rules when he works with someone – they spend time in the funky studio space that adjoins his home, banging out ideas. While sequestered in that space, an aesthetic vision emerges.


No doubt Nashville has changed since Angelo first set foot here, transforming from a quiet Southern town where country music reigned to a bustling city that's trying to embrace new ideas even as it grapples with its sometimes complicated history. Angelo has been along for the ride, rising and changing to meet the challenges of this new landscape in his own mercurial way.