In the past three years, Jeshua Marshall has gone from barely being around to one of the more visible players in Bend’s music scene.

The bassist, guitarist and songwriter is still best known as the bassist for long-running folk-punk institution Larry and His Flask, which he co-founded with brother, drummer Jamin Marshall, in 2003.

The band gained national attention when it shifted from straightforward punk to its signature high-energy, acoustic-based sound in the late 2000s, and high-profile shows with Warped Tour and opening for Streetlight Manifesto and Frank Turner kept it on the road for long stretches.

“I lived in California for a little bit, but mostly, I was always home-based here,” Marshall said while sitting outside Palate coffee recently. “And so, we’d be gone so much, when I’d come back, I’d have no idea what’s going on with the local music scene. So I’m like, what, what band? What? Who’s doing what?”

When the Flask went on hiatus in 2014, Marshall, who has been a full-time musician for most of his adult life, suddenly had plenty of time on his hands. He plays in at least five other bands in addition to the Flask, which began touring again last year: the Latin-tinged roots rock sextet Guardian of the Underdog, which he fronts; The Hot Club of Bend; The Nomads, Onward, Etc.; and the newly formed Warhoot. Guardian of the Underdog, which primarily features Marshall’s songwriting, will open for Boston singer-songwriter Absinthe Rose and Portland’s Dogtooth & Nail at one of its favorite local venues, Volcanic Theatre Pub, on Thursday. Also on Thursday before that show, Marshall will sit in with songwriter Tom Vandenavond at Palate Coffee.

“I’ve just been playing music full time, and so when Larry stopped touring, I was just like, well, what do I do with my time?” Marshall said. “I don’t want to stop playing music all the time; then I’ll lose my chops and be bored and not be fulfilling my passion. So I was just like, since I’m not touring all the time, in Central Oregon, at least I can play with a lot of different people and expand. Every group I play with is a different style, from jazz to rock ’n’ roll to bluegrass, country and whatever Larry is — punk rock.”

Though Guardian of the Underdog has existed since 2014, Marshall has taken his time establishing the band. With the Flask planning to record its first album in nearly five years later this year, not to mention Marshall’s other band commitments, it can be challenging to find time to dedicate to the group.

Guardian started as a solo project that grew out of the songs Marshall was writing after the Flask’s hiatus. Marshall still plays some solo out-of-town shows under the moniker.

“I wanted to do solo, and then I was like, I love playing with drums and everything,” he said. “It’s kind of been evolving, and slowly — we’ve been taking it really slow. I haven’t been pushing it. I’m playing in a lot of different groups, so I put it on the back burner a lot of the time, but whenever we have an opportunity to play, we take it.”

Initially, Marshall began playing these new songs with Jamin on drums under the name Marshall Law (referencing a song of the same name written about the brothers by California folksinger Willy Tea Taylor). When Jamin moved to the Caribbean, Marshall dropped the name and began reconnecting with musician friends he’d known since school — first drummer Alán Viramontones, who introduced him to trumpeter Miguel Mendoza; then bassist Davey Hemm and cellist Billy Mickelson (who also performs solo as Third Seven). Guitarist Seth Acquarolo, a new face on the local scene, joined the group recently after moving to the area from Philadelphia.

Known for his highly physical performances on upright bass with the Flask, Marshall had to build up confidence in his singing and guitar playing. Though he writes all his songs, including Flask material, on guitar, it’s his second instrument. Vocally, he also faced challenges, including an allergy as a kid that necessitated a tracheotomy.

“I have to break that scar tissue up to be able to sing,” he said. “… And then just playing at open mics a lot, that’s what helped me feel like I could perform in front of people. Because at open mic, it’s like, whatever. If you suck, it’s not as big of a deal; people kind of expect that anyway.”

Musically, Guardian keeps the energy of the Flask while taking a less frantic approach, integrating elements of reggae, jazz, Latin and roots rock. Marshall’s lyrics are often heavily political, as on “Down With the Party Killers,” an impassioned protest against police violence that Marshall plans to turn into a solo music video using footage he shot while staying in Palestine earlier this year.

Marshall’s activism carries on beyond his music. Through his work with local nonprofit Rise Up International, Marshall traveled to the Standing Rock protests in the Dakotas in November and shot video for Central Oregon Daily of police turning water cannons on protesters. The experience was “heart-opening and just incredible” for Marshall, who has some Native American blood.

“One thing that was really cool that the people and the leaders there were expressing that I think we often forget is that we’re all indigenous,” he said. “We’re all from this planet, so we all need to remember our relations with the Earth and not view it as just a resource or a commodity that is infinite. If we just keep on the path that we’re on, we’re gonna make this planet unlivable.”

“I wanted to do solo, and then I was like, I love playing with drums and everything,” he said. “It’s kind of been evolving, and slowly — we’ve been taking it really slow. I haven’t been pushing it. I’m playing in a lot of different groups, so I put it on the back burner a lot of the time, but whenever we have an opportunity to play, we take it.”Jeshua Marshall, Guardian of the Underdog frontman

What: Guardian of the Underdog opening for Absinthe Rose, Dogtooth & Nail

When: 9 p.m. Thursday

Where: Volcanic Theatre Pub, 70 SW Century Drive, Bend

Cost: $8 plus fees in advance, $10 at the door

Contact: volcanictheatrepub.com or 541-323-1881