So what is it about Ernest Shackleton and the Endurance? Why so much excitement about the recent discovery of an old wooden ship at the bottom of the Antarctic ocean? In my book Celtic Lightning, I devote a chapter to Irish-born Shackleton, noting that once upon a time, he came that close to becoming an Arctic explorer. “Now my eyes are turned from the South to the North,” Shackleton wrote in 1920, “and I want to lead one more expedition. This will be the last…. to the North Pole.”

Shackleton visited Canada and drummed up financial support among Canadians. He also gleaned promises from the Canadian government, which then, inexplicably, withdrew them. The explorer eventually secured funding from a wealthy school friend, but too late in the season. He cancelled the northern voyage and looked again to the south. But all that came later  — after his great moments. Shackleton’s achievements in the Antarctic were such that people around the world often study them as models of leadership, perseverance, and survival. In Celtic Lightning, I present the Shackleton story from cradle to grave. But here’s a brief excerpt . . .

Early in 1914, Ernest Shackleton published his plan for an Imperial Trans-Antarctic Expedition. He would use two ships, the Endurance and the Aurora, and establish bases on opposite sides of Antarctica. Thanks to his iconic status, he raised the necessary funds and then published one of the most famous advertisements in exploration history: “Men wanted for hazardous journey. Low wages, bitter cold, long hours of complete darkness. Safe return doubtful, honour and recognition in event of success.” Shackleton had to sift through more than 5,000 applications from those who wished to join him. He selected men unconventionally, for temperament as much as technical ability, and eventually chose fifty-six men, assigning twenty-eight to each ship.

In July 1914, with preparations nearing completion, the First World War erupted. Winston Churchill, the First Lord of the Admiralty, had been sceptical of the voyage, arguing that the South Pole had already been discovered: “What is the point of another expedition?” But in August, despite the war, he wired his approval: “Proceed.” And the two ships sailed from England on what would one day be regarded as the last great expedition of the Heroic Age of Polar Exploration.

Shackleton delayed his own departure and caught up with the Endurance in Argentina. From there, thanks to the example of Roald Amundsen, who had learned from the Inuit, the ship sailed with 69 Canadian sled dogs. Nine or ten of these, hitched into a team, could haul 1,000 pounds. Early in December, having sailed to South Georgia Island, Shackleton continued south but encountered heavy ice. The Aurora, torn from its moorings in a storm, and unable to re-enter the ice, struggled back to New Zealand.

By January, the Endurance was frozen fast. And on February 24, Shackleton converted the trapped ship into a winter station. In September, as the southern spring brought warmer temperatures, the breakup of the ice put pressure on the ship’s hull. Late in October, water began pouring into the Endurance. Shackleton gave the order to abandon ship and transferred men, dogs, and provisions onto the ice.  On November 21, 1915, the wreck slipped beneath the surface. “At 5 p.m. she went down,” he noted. “I cannot write about it.”

Now began the great test of Shackleton’s perseverance. For more than four months, in freezing cold temperatures, he and his men camped out on a massive, drifting ice floe. When in April 1916 it began breaking up, he ordered his men into the three remaining lifeboats. After five days in difficult seas, they landed on barren Elephant Island, having travelled a total of 560 km from the wreck of the Endurance. This isolated spot, far from shipping lanes, offered subsistence living on seals and birds but no hope of rescue.

Having failed in his original objective, Shackleton vowed to bring all his men home safely. He decided to undertake an open-boat journey through notoriously stormy seas to the whaling stations of South Georgia, 800 nautical miles or 1480 km away. On April 24, 1916, with five companions, he set out in a 6.9-metre (23 foot) lifeboat with a makeshift deck and canvas. The boat nearly capsized several times. But two weeks later, thanks to an extraordinary feat of navigation and despite a fog, the sailors could discern the cliffs of South Georgia. Hurricane-force winds prevented a landing until the following day, May 9.

The rocky beach where finally Shackleton went ashore was bleak and empty. But rather than risk further voyaging, the hardy explorer decided to make for the whaling stations on the other side of the island. This meant hiking and climbing 50 km across unknown, glaciated mountains. He set out with two men, one of them that Irish giant, Tom Crean, who had piloted the lifeboats to Elephant Island. Incredibly, after a thirty-six hour march through icy, rocky, and mountainous terrain, the trio reached the whaling station named Stromness on May 20.

Shackleton sent a boat to collect the three men on the other side of South Georgia, and set to work planning the rescue of the twenty-two still waiting on Elephant Island. After trying and failing to depart three times, Shackleton gained control, thanks to the Chilean government, of a small tug. On August 30 1916, with a whaler behind him, Shackleton reached Elephant Island and rescued his remaining men. Before leaving the south, Shackleton also rescued the so-called “Ross Sea party” who had got stranded in McMurdo Sound after the Aurora was driven out to sea. This group had lost three men.

Such was the expedition that turned Shackleton from merely famous to legendary. Back in England, with the First World War still raging, he volunteered for the army but was rejected because of a heart condition.In 1919, he published South, an account of the Endurance expedition. The following year, he began proposing yet another expedition — this one into the Beaufort Sea area of the western Canadian Arctic. He acquired a 125-ton whaler and renamed it the Quest, but then changed his destination: he would voyage once more to the Antarctic, and there attempt a circumnavigation of that continent.

In September 1921, having been joined by many former crew members, he sailed from England. In Rio de Janeiro, Shackleton suffered a suspected heart attack. But he refused treatment, resumed voyaging, and reached South Georgia on January 4, 1922. In the early hours of the next morning, Shackleton suffered a fatal heart attack. He was buried, at the request of his wife, on his beloved South Georgia Island.