When you ask Rachel Jackson about Oklahoma's "radical" past, she has plenty of examples.
"First off, most people don't know that Oklahoma had a really strong organized labor and Socialist Party presence," says Jackson, who has been researching all of this for a dissertation at the University of Oklahoma. "At the time of statehood in 1907, it had the largest Socialist Party state chapter in the country."
Then there's the anti-World War I march on Washington that culminated in the Green Corn Rebellion in 1917. And the mistaken notion that the term Okies refers exclusively to poor whites, something she says overlooks the contributions of African Americans and Native Americans to the state's history.
Jackson will be one of the historians leading a weeklong tour in July sponsored by the San Francisco-based human rights organization Global Exchange. It's called Radical Oklahoma, a tour intended to shed some light on an interesting history in a state known for being conservative.
"It's been fun thinking about how you present radical history in the form of a vacation package," she says. "How do you emphasize radical history when it has been suppressed and erased?"
Tour stops include the site of the Green Corn Rebellion, the Muscogee Nation Museum in Okmulgee to learn about uprisings by Native Americans, the site of all-black townships that once existed in the state, and some state parks too.
Participants then spend four days at the Woody Guthrie Folk Festival in the singer's hometown of Okemah.
And there might be a history lesson in this tour for Californians. One can't help but wonder how the radical winds affected Guthrie and Dust Bowl migrants who came to the Golden State to start over.
When: The tour runs from July 7-14. 
Price: $950 per person, double occupancy. It includes lodgings, van transportation, airport transfers, trip leader and history docents (including Jackson), admission to programs and activities, and two meals a day. Airfare to and from Oklahoma as well as some meals are extra.