A super-rare poster depicting the legendary elephant that inspired Disney's 1941 classic "Dumbo" is set to be sold at auction for up to $6,300.

The cloth canvas banner shows real-life elephant Jumbo standing on a podium, waving a flag from his trunk that reads "London Zoo Circus,"  where the animal resided from 1865 to 1882.

It is believed that, after almost 20 years at the famous London Zoo, the majestic Jumbo was sold for 2,000 pounds sterling to American entertainer P.T Barnum, who inspired the 2017 film "The Greatest Showman."

Jumbo was then transported to the U.S., despite much public outcry in the U.K., and became the main attraction of Barnum and Bailey's Circus' "Greatest Show on Earth."

In 1882, 100,000 schoolchildren wrote to Queen Victoria, begging her to halt the sale of the elephant.

Leading English art critic John Ruskin, a fellow of the Zoological Society, branded the sale of the elephant to Barnum and Bailey's Circus as "dishonorable to common humanity".

In February 1882, Ruskin wrote: “I, for one of the said fellows, am not in the habit of selling my old pets or parting with my old servants because I find them subject occasionally, perhaps even periodically, to fits of ill temper.

The cloth canvas banner shows real-life elephant Jumbo standing on a podium, waving from his trunk a flag that reads 'London Zoo Circus' - where the animal resided from 1865-1882. (Credit: SWNS)

"I not only regret the proceedings of the council, but disclaim them utterly, as disgraceful to the city of London and dishonorable to common humanity."

Jumbo became the star attraction of Barnum & Bailey’s "Greatest Show on Earth" and the circus earned $1.75 million in their 31-week season.

On May 30, 1884, Jumbo was one of Barnum's 21 elephants to cross the Brooklyn Bridge to prove that it was safe, after 12 people died during a stampede caused by mass panic over collapse fears a year earlier.

Jumbo died the follwoing year after he was hit by a train in Ontario, Canada, as he was led back to his boxcar after a performance.

The banner, being sold by Chorley's Auctioneers in Cheltenham, Glos., is oil on thick cloth canvas.

It is mounted floating in a contemporary frame with museum grade glass to preserve and enable viewing of the rear of the banner.

The two-dimensional pose and bold silhouette make this a wonderful piece of British Folk Art.

It is expected to fetch between $3,800 and $6,300 at auction on July 23 and July 24.