The Backbone Campaign, the Vashon-based organization known for its eye-popping mix of giant puppets and progressive politics, will hold a benefit called “Songs of Freedom: People Power Music Across the Decades,” featuring a full roster of Island singers, songwriters and musicians. The benefit — 7:30 p.m., Saturday, June 21, at Red Bicycle Bistro & Sushi — will also include an auction of items donated by Island businesses.

“Songs of Freedom” is the latest installment in a series of Backbone Campaign themed concert fundraisers. Past themes have included the Beatles and “Bob and Bob,” the songs of Bob Marley and Bob Dylan.

This time around, Bill Moyer, Backbone’s executive director, invited artists to “celebrate the music that continues to inspire us to have the backbone to stand up for our hopes for a better future.” Moyer promised “classic songs of liberation, from Woody Guthrie to Bruce Cockburn, Joan Baez to Ani de Franco, John Lennon to Michael Franti.”

Pete Welch, who is helping to organize the event, billed it as “a gathering of community, like the old days, where you see your neighbors and friends and share a wonderful night of music together.”

More than two dozen musicians and groups — including such Island stalwarts as Subconscious Population, Bob Krinsky, John Browne and Sarah Christine — have already signed up to participate. Steffon Moody has been tapped to emcee the evening, and Kevin Joyce will serve as auctioneer.

The Backbone Campaign will also reveal more about its upcoming plans, including its “Procession for the Future,” which Moyer described as “a visually compelling and living spectacle, presenting a progressive platform in parade form,” and “a celebration of progressives’ propositional ideas.”

Elements of the parade will be seen by Islanders at Vashon’s Strawberry Festival, prior to a national tour on a donated bus that runs on vegetable oil. Stops on the tour will include the Democratic National Convention in Denver and the Republican National Convention in Minneapolis.

All money raised at the “Songs of Freedom” benefit will help fund the parade’s national tour, anticipated to cost around $17,000.

Tickets to “Songs of Freedom” cost $15 and are available at Books by the Way and Vashon Bookshop. All ages may attend until 9 p.m., after which the event becomes 21 and up.