The first viewing of the Johnny and June Carter Cash auction at Sotheby’s caused a stir, but probably not the sort the auction house had been expecting. It wasn’t fans of the late singer, delirious over his knee-high alligator cowboy boots [LOT 208] or June’s acoustic guitars [LOT 95]. Rather, several hundred protesters came together outside Sotheby’s Upper East Side home to protest the event, held to honor the GOP delegates from Tennessee. Protesters wore black, carried cardboard guitars, sang Cash songs, and shouted, “Whose Cash? Our Cash. RNC go home!”

Now that the GOP has departed, the focus can go back to the items in the Cash sale, which runs September 14 to 16, and what they reveal about the legendary first family of country music.

Fittingly, the 769-lot auction originated from one of the most politically divisive of issues: taxes. John Carter Cash, the couple’s 33-year-old son, said the sale represented about one third of his parents’ belongings (Johnny once said June had a “black belt in shopping”), and they are being sold to cover the estate taxes. Sotheby’s has coyly estimated the sale to bring $1.5 million, but like all other celebrity sales, the fame factor will push prices higher.

And the tide of fame just keeps on rising. The Cashes sold more than 50 million records during their lifetimes, and Cash is the only musician inducted into the Rock and Roll Hall of Fame, the Country Music Hall of Fame, and the Songwriter’s Hall of Fame. This month brings the auction along with the publication of an authorized biography of Cash on September 12, the one-year anniversary of his death at 71. Also in the works is a movie with Joaquin Phoenix playing the battered balladeer and Reese Witherspoon as the graceful June.

Predictably, the sale includes a trove of music memorabilia: gold records, handwritten lyrics, and – the best things in the sale – fantastically chic vintage outfits. Interspersed among the musical lots are garden-variety silver, china, and glass – things so ordinary that they wouldn’t be found for sale at Sotheby’s without the gold-record provenance. Baroque wooden furniture and mundane driver’s licenses and passports round out the sale. The Cashes’ five children evidently allowed Sotheby’s to sweep their parents’ home clean – in the same spirit as the everything-and-the-kitchen-sink auction held recently on behalf of Katharine Hepburn’s beneficiaries. All of the objects come from the Cash lakeside home in Hendersonville, Tenn. – which is itself for sale – and the now closed House of Cash Museum.

What’s likely to get fans and buyers most excited are the items connected to the Cashes’ storied musical career. The lots include gold records and concert posters, 50 guitars and banjos, and seven Grammy awards. This material spans all their decades in the business, even including scuffed brown leather boots June wore when she was a member of the popular Carter Family singing group in the 1940s (est. $300-$500).

Cash, who picked cotton as a boy growing up in Arkansas, got his start in music after serving in the Air Force. In 1954 he auditioned for Sun Records owner Sam Phillips, and a star was born. A group of three unplayed Johnny Cash Sun 45 records, found in his wardrobe closet, with hits such as “I Walk the Line” and “Folsom Prison Blues,” will undoubtedly blast by the $200-$400 estimate.

Some of the highest-priced musical memorabilia includes a 1955 spiral notebook with handwritten lyrics (est. $10,000-$20,000) and a 1960s Grammer custom acoustic guitar (est. $10,000-$20,000). But the vast majority of lots are far less expensive, such as a group of prison memorabilia – including a striped prisoner’s jacket and a pair of cufflinks (decorated with an image of a prison door) – given to Cash by the Folsom Prison warden (est. $800-$1,200). Cash received the gifts in 1968 after performing at the prison for 2,000 inmates. (Cash not only sang about and in prisons, he also did hard time. He was thrown in a Mexican jail in 1965, caught trying to smuggle amphetamines into the United States.)

But I think the most desirable items in the sale are the chic and restrained clothing. The Cashes had a distinctive style, shaped by the gifted designer Manuel. He is famous in the music world, best known for embroidering red lips for the Rolling Stones and skulls and roses for the Grateful Dead. He inspired every wanna-be rhinestone cowboy in Nashville with his designs.

It was clear that the soulful Cash was not cut out for sequins. The “Man in Black” was launched as Manuel devised an elegant rueful look for the singer. Using delicate natural motifs such as flowers and acorns, Manuel created such works as a black three-piece suit with intricate hand-stitched flowers (est. $4,000-$6,000). For the petite June, Manuel created gorgeous suede Indian style dresses, such as a beaded and fringed size-8 shift (est. $1,000-$1,500), which might sound tacky to Prada disciples, but is not.

It will be interesting to see what happens with the sale’s highest-priced lots. They include two bucking bronco bronze sculptures by artist Frederic Remington, each estimated at $40,000-$60,000. The other high-ticket items represent the modern day bronco – the car. A 1987 Rolls-Royce Silver Spur in cobalt blue with just 27,000 miles is estimated at $50,000-$60,000. But, considering the Cashes’ fame as country stars, it is possible that their other ride might attract even more action on the bidding block: a 2002 black Ford pickup truck with just 15,000 miles on the odometer (est. $20,000-$30,000).

Cash got the truck as part of a deal to do Ford commercials in 2001, and it’s likely that bidding will be fierce, regardless of the fine print. At the back of the auction catalog, in eye-witheringly small print, Sotheby’s legal eagles proclaim that both the Rolls and the pickup are “being sold exclusively for off highway use.” Sotheby’s makes no assurances that the cars are “roadworthy.” This disclaimer is entirely fitting for a sale where the last reason anyone is buying anything is to actually use it. Their belongings are desirable only because Johnny and June did.