lingers over claims that DiCaprio was raped by the bear- twice - in the movie opening Christmas day

Viciously mauled by a 'monster' grizzly bear, bloodied and left to die in the wilderness with no weapons or food, Hugh Glass dragged himself across rivers and rough terrain 200 miles to seek vengeance on the two men who abandoned him: it's the amazing true story of the American frontier trapper who inspired Leonardo DiCaprio's latest film.

The brawny and bearded mountain man, an expert marksman and hunter, earned his heroic stature after battling and surviving an attack by a massive female grizzly bear during an expedition – part of the American fur trade -- to the Rocky Mountains in 1823.

His incredible story has become legend, the subject of at least a half-dozen books, including a 2013 biography entitled 'Here Lies Hugh Glass: A Mountain Man, a Bear, and the Rise of the American Nation,' and now a film - The Revenant- starring DiCaprio as Glass that opens Christmas day.

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Fearless: The brawny and bearded Glass, an expert marksman and hunter, earned his herculean stature after battling and surviving an attack by a massive female grizzly bear during an expedition – part of the American fur trade -- to the Rocky Mountains in 1823

Star turn: Glass's incredible story has become legend, the subject of at least a half-dozen books and now a film - The Revenant- starring DiCaprio as Glass that opens Christmas day

Controversy surrounding the film based on a popular novel about Glass, was ignited when the Drudge Report claimed that DiCaprio's Glass was graphically raped by a massive bear twice.

Drudge went on to reveal that the 'bear flips Leo over and thrusts and thrusts during the explicit mauling.'

But the film's studio, Fox, issued a strong denial: 'As anyone who has seen the movie can attest, the bear in the film is a female who attacks Hugh Glass because she feels he might be threatening her cubs. There is clearly no rape scene with a bear.'

The true story of Hugo Glass is sensational enough.

Glass was born in 1780, four years after America declared its independence, and with the Revolutionary War between Great Britain and America's original thirteen colonies still raging. He was the son of Irish parents who had settled in the Commonwealth of Pennsylvania.

Among the many trappers, pioneers and explorers of the American West like Lewis and Clark, Hugh Glass was not well known - until his tale of the bear attack was revealed after his death.

Overnight, he became a frontier folk hero, inspiring newspaper articles and books. Oddly, an epic poem, 'The Song of Hugh Glass,' published in 1915 barely mentions Glass's near-fatal wrestling match with the possessive mama grizzly but rather his battles with hostile Indians, and fellow trappers who betrayed him.

Flap: Controversy surrounding the film was ignited when the Drudge Report claimed that DiCaprio's Glass was graphically raped by the massive bear twice. The studio has denied it

According to one story, Glass was captured by privateers off the coast of Texas in 1816, and forced to become a pirate for two years. He allegedly escaped by swimming to shore near what is now Galveston.

Later, the legend goes, he was captured by Native Americans, spent a few years with the tribe, and married a squaw.

In the early 1820s the Missouri Gazette and Public Advertiser began running an advertisement placed by an Army general seeking men to join him in the fur trade, a lucrative business in those days.

The route of the 1823 odyssey of Hugh Glass from the forks of the Grand River to Fort Kiowa

Glass, in his early thirties, responded along with a number of so-called mountain men who joined the enterprise that became known as 'Ashley's Hundred,' named for General William Henry Ashley who was behind the moneymaking enterprise.

But there was much trouble ahead for the expedition, and especially for Hugh Glass, a man who seemed to have little luck in life.

In the Spring of 1823, while traveling up the Missouri River, warriors of the semi-nomadic Arikara Indian tribe attacked Ashley's Hundred. There was a vicious battle and Glass was wounded, taking a bullet in one of his legs.

That brought an end to the trek for some of the members of Ashley's Hundred, including the wounded Glass.

But even worse was in store.

In August, 1823 Glass came face to face with one angry mama Grizzly. It happened by accident.

Glass had been hunting for game in Perkins County, South Dakota, when, according to an account in the Milwaukee Journal newspaper a century later, he suddenly came upon a monster female grizzly bear with her her two cubs. She rose and attacked him before he had the time' to fire his weapon, or try to escape.

'The bear seized him by the throat and lifted him from the ground. Then hurling him down, the ferocious beast tore off a mouthful of his flesh and lumbered to her cubs, which were close by.

'Glass now tried to escape, but the bear, followed by her cubs, attacked him again. Seizing him by the shoulder she crunched his hands and arms between her teeth.'

The Milwaukee Journal article describing the included a frightening drawing by artist Charles M. Russell of a ravaged and bloodied Glass holding on to a tree limb as a giant grizzly bear, standing erect on its hind legs, was trying to drag him away in order to kill him. In the background is a frolicking grizzly cub whose mother was protecting it from the great white hunter

The grizzly bear averages about six feet in length from 'nose to tail tip,' although some measured as high as fourteen feet. They weigh at least five hundred pounds

The article included a frightening drawing by artist Charles M. Russell of a ravaged and bloodied Glass holding on to a tree limb as a giant grizzly bear, standing erect on its hind legs, was trying to drag him away in order to kill him. In the background is a frolicking grizzly cub whose mother was protecting it from the great white hunter.

The article pointed out that the grizzly bear averages about six feet in length from 'nose to tail tip,' although some measured as high as fourteen feet. They weigh at least five hundred pounds.'

It called the grizzly a 'powerful brute,' and noted, 'The female, when her cubs are small, is savage and dangerous' and when roused – the mistake Glass had made – 'shows terrible rage and strength.'

Glass, bleeding profusely and in agonizing pain, had given himself up for dead, when other members of his hunting party came upon the grisly scene.

Shots were fired by the critically injured Glass's compatriots, and one of the cubs, half-grown – was killed. More shots were fired and the furious mother bear was fatally brought down – her huge body actually falling on the near-dead Glass.

Incredibly, he survived the deadly attack, but 'his whole body was mangled, he could not stand and suffered excruciating pain. No surgical aid could be given and it was impossible to move him.'

One of the officers in the group, an Army major, offered two underlings a sum of eighty-two dollars to stay with Glass until he died because no one believed he'd make it.

The duo watched over him for a full five days, but he had the willpower to ward off death.

When he failed to succumb to his severe injuries, they took his rifle and his other belongings and abandoned him with no shelter or any means of defense. When the two reached their group they claimed Glass had died, and that they had given him a burial.

An historic marker that overlooks Shadehill Reservoir in northwestern South Dakota tells the saga of Glass

But Glass's will to survive was extraordinary.

According to one account, the critically injured Glass had a broken leg, open and festering wounds, bites from the battle with the bear that had exposed bare ribs, and there were major cuts on his back.

Incredibly, he set his own leg, wrapped himself in the bear hide that had been the shroud left by the men who abandoned him. And amazingly, he let maggots eat the dead flesh on his body as a way to prevent gangrene.

When he was up to it he reportedly crawled overland, and for river crossing he crafted a raft in order to reach the first civilized settlement, as far as 200 miles away.

It was a treacherous trek that took him six weeks, subsisting mainly on wild berries and roots.He was determined to track down the two men who had abandoned him.

His trek would take him to a trading post, along the way eating meat from a buffalo calf that had been attacked by wolves – driven off by Glass who brandished only a stick.

When he reached the trading post, he rested, regained his health, and then joined a group of trappers in hopes of finding the men who had left him for dead.

He had an 'overwhelming desire for revenge.'

He eventually tracked down one of them at Fort Atkinson, near what became the city of Omaha. The other man he sought had disappeared. Glass, however, was talked out of killing, under threat of a murder charge, a trial, and execution.

Not much is known of Glass's later life, other than he worked as a hunter for Fort Union, at the mouth of the Yellowstone River.

One account of his death in 1833 at 53 was given by a visitor at Fort Union, reported by the Milwaukee newspaper.

'Old Glass with two companions had gone to Fort Cass to hunt bear on the Yellowstone, and as they were crossing the river on the ice all three were shot and scalped by a war party of 30 Aricaras.'