In 1914, the British explorer Ernest Shackleton set sail from London for Antarctica with 28 men and a ship called the Endurance — and 22 months later, after the ship was crushed by pack ice and the men had lived on drifting ice floes and a barren island for nearly two years, every one of them came home alive

On Saturday, 8 August 1914 — five days after the British declaration of war against the German Empire that would produce the subsequent four-year catastrophe of the First World War, and following a specific one-word instruction from the First Lord of the Admiralty Winston Churchill authorising the expedition to “proceed” despite the outbreak of hostilities — the three-hundred-ton wooden barquentine Endurance, originally built as the Polaris for a subsequently cancelled Belgian Arctic expedition and renamed by its new owner after his family motto (“By endurance we conquer”), departed the Devonport dockyard at Plymouth under the command of the 42-year-old New Zealand-born ship’s captain Frank Worsley, bound for the Antarctic continent via Buenos Aires and the South Georgia whaling station at Grytviken. Aboard the ship were 27 expedition crew members. The 28th member of the expedition — its 40-year-old Anglo-Irish leader Sir Ernest Henry Shackleton, who had been detained in London by expedition administrative business — travelled separately by faster steamer and rejoined the Endurance at Buenos Aires in October 1914. On 5 December 1914, the completed expedition departed South Georgia. Twenty-two months later, on 3 September 1916, all 28 members of the Weddell Sea party returned to the Chilean port of Punta Arenas alive.

None of them had crossed the Antarctic continent. None of them had even set foot on it. The specific stated objective of the Imperial Trans-Antarctic Expedition of 1914-1917 — to be the first human beings to cross the 1,800-mile geographical span between the Weddell Sea coast and the Ross Sea coast of the Antarctic continent on foot — was not accomplished by the expedition or by anyone else for approximately the subsequent 44 years, until Sir Vivian Fuchs’s motorised Commonwealth Trans-Antarctic Expedition eventually completed the crossing in 1957-58. What the 1914-1917 Shackleton expedition did accomplish, entirely as a byproduct of the specific chain of catastrophic operational failures that made accomplishing the original objective impossible, was the substantially most substantive single feat of small-group survival leadership in the recorded history of modern exploration — and it did so under specific environmental and material conditions that essentially every subsequent survival-psychology analysis has concluded should, on the strict statistical probabilities of the underlying situation, have produced the deaths of most or all of the men involved.

As detailed in History.com’s summary of the Endurance expedition’s specific survival trajectory across 1914-1916, the Endurance became trapped in the Weddell Sea pack ice on 19 January 1915, approximately six weeks after departing South Georgia and approximately 85 miles from the intended landing site at Vahsel Bay. The ship spent the subsequent nine months progressively drifting northward with the moving ice pack, unable to break free, while the 28 men aboard progressively prepared for the specific outcome that Shackleton and Worsley had recognised by approximately March 1915 was substantially inevitable. On 27 October 1915, the accumulated pressure of the surrounding pack ice broke the ship’s hull. On 21 November 1915, what remained of the Endurance sank beneath the ice. The 28 men set up a canvas-tent camp on the surrounding ice floe, salvaged what supplies and equipment they could recover from the broken ship (three lifeboats, the ship’s ration stores, some of the dogs, the photographic plates that the Australian expedition photographer Frank Hurley had taken across the preceding months), and settled in to wait for the drift of the ice pack to carry them close enough to an inhabited land mass that they could reach it in the lifeboats.

The five months on the ice

The specific interval that the 28 men subsequently spent camped on drifting sea ice — first at “Ocean Camp” from November 1915 to December 1915, then at “Patience Camp” from December 1915 to April 1916 — was, by every measurable metric of contemporary polar survival medicine, substantially longer than any comparable group of humans had previously survived under comparable conditions and returned intact. Per Live Science’s reconstruction of the specific environmental conditions the Endurance survivors faced during their five months on the drifting sea ice, the ice floes on which the camps were established were approximately ten feet thick, floating over Weddell Sea waters that reached depths of approximately 11,250 feet below the ice. Air temperatures across the Antarctic winter of 1916 regularly reached −20°C or lower. The 28 men slept in canvas tents that provided essentially no insulation against ambient temperatures. Their diet consisted of the shipboard ration stores they had salvaged, supplemented by penguin and seal meat when the animals could be caught, and (progressively as the food stores exhausted) the meat of the sled dogs they had brought from South Georgia and which Shackleton had ordered shot in stages across the ice-camp period. The specific ice floe on which Patience Camp was established was slowly breaking apart across the March and early April of 1916 as the drifting pack ice reached warmer subantarctic latitudes. On 9 April 1916, the crew launched the three salvaged lifeboats into open water and, across the subsequent seven days of exposure to freezing Antarctic conditions, rowed the boats approximately 100 miles to Elephant Island — a small uninhabited volcanic outcrop at the northern edge of the Antarctic archipelago that was the first land any member of the expedition had set foot on in the 497 days since the Endurance had departed South Georgia.

The 800 miles

Elephant Island offered the 28 men a substantially precarious survival platform: exposed rock, no vegetation, no fuel, essentially no shelter beyond the two overturned lifeboats the crew subsequently assembled into makeshift accommodation. As reported in Aurora Expeditions’ detailed chronological timeline of the specific Endurance expedition survival sequence across 1914-1916, Shackleton concluded within days of the Elephant Island landing that no rescue would arrive at the island without the specific human intervention of some member of his own party. On 24 April 1916, Shackleton, Worsley, Crean, McNish, McCarthy, and Vincent departed Elephant Island in the 22.5-foot lifeboat James Caird — reinforced with materials scavenged from the two remaining lifeboats — on the specific navigational objective of sailing 800 miles across the Southern Ocean to South Georgia, where the whaling stations at Grytviken and Stromness could organise a subsequent rescue mission for the 22 men remaining at Elephant Island. The 16-day James Caird voyage — conducted through hurricane-force winds and freezing conditions in an open boat that was continuously taking on water and required constant bailing to remain afloat — has been described by essentially every subsequent polar-navigation authority as one of the substantially most improbable small-boat voyages in the recorded history of maritime exploration. On 10 May 1916, the six men landed on the uninhabited southern coast of South Georgia. Shackleton, Worsley, and Crean subsequently spent 36 hours traversing on foot the substantially unexplored interior mountain range of South Georgia to reach the Stromness whaling station on the northern coast. Four failed rescue attempts subsequently departed for Elephant Island across the following four months. On 30 August 1916, the Chilean navy tug Yelcho reached Elephant Island and evacuated the remaining 22 men. All 28 members of the Weddell Sea party of the Imperial Trans-Antarctic Expedition returned to the port of Punta Arenas alive.

As detailed in the Shackleton Company’s institutional account of the Imperial Trans-Antarctic Expedition and its subsequent legacy, the specific survival outcome of the Weddell Sea party was not, in fact, uniformly duplicated across the broader expedition. The separate Ross Sea party, aboard the ship Aurora, which had been assigned the task of laying supply depots on the opposite coast of Antarctica for the Shackleton overland crossing that never happened, lost three men (Aeneas Mackintosh, Victor Hayward, and Arnold Spencer-Smith) across their own separate 20-month Antarctic ordeal — a specific fact that the popular subsequent narrative of the Shackleton expedition has substantially deemphasised in favour of the more dramatic 28-of-28 survival story of the Weddell Sea party. The wreck of the Endurance itself, which had sunk beneath the Weddell Sea ice on 21 November 1915, was discovered on 5 March 2022 by the Endurance22 expedition led by the polar geographer Dr John Shears — 3,008 metres beneath the Weddell Sea, approximately four miles from the coordinates that Frank Worsley had recorded in his 1915 navigation log — 100 years to the day after Ernest Shackleton’s own funeral on South Georgia in March 1922. Shackleton himself had died of a heart attack at Grytviken on 5 January 1922, at age 47, at the beginning of a fourth Antarctic expedition. He was buried at the whaling station where the Imperial Trans-Antarctic Expedition had begun.