1914–1917: Map showing the sea routes of
, planned overland route of the transcontinental party, and supply depot route of the
Ross Sea party
Voyage of Endurance
Drift of Endurance in pack ice
Ice drift after Endurance sinks
Voyage of James Caird
Planned transcontinental route
Voyage of Aurora to Antarctica
Drift and retreat of Aurora
Supply depot route
Despite the public acclaim that had greeted Shackleton's achievements during the
Nimrod Expedition in 1907–09, the explorer was unsettled, becoming—in the words of British skiing pioneer Sir
Harry Brittain—"a bit of a floating gent".
 By 1912 his future Antarctic plans depended on the results of Scott's
Terra Nova Expedition, which had left
Cardiff in July 1910, and on the concurrent
Norwegian expedition led by
Roald Amundsen. The news of Amundsen's conquest of the
South Pole reached Shackleton on 11 March 1912, to which he responded: "The discovery of the South Pole will not be the end of Antarctic exploration".
 The next work, he said, would be "a transcontinental journey from sea to sea, crossing the pole".
 He was aware that others were in the field pursuing this objective. On 11 December 1911, a German expedition under
Wilhelm Filchner had sailed from South Georgia, intending to penetrate deep into the Weddell Sea and establishing a base from which he would cross the continent to the Ross Sea.
 In late 1912 Filchner returned to South Georgia, having failed to land and set up his base.
 However, his reports of possible landing sites in
Vahsel Bay, at around 78° latitude, were noted by Shackleton, and incorporated into his developing expedition plans.
News of the deaths of Captain Scott and his companions on their return from the South Pole reached London in February 1913. Against this gloomy background Shackleton initiated preparations for his proposed journey.
 He solicited financial and practical support from, among others,
Tryggve Gran of Scott's expedition, and the former Prime Minister
Lord Rosebery, but received no help from either. Gran was evasive, and Rosebery blunt: "I have never been able to care one farthing about the Poles".
 Shackleton got support, however, from
William Speirs Bruce, leader of the
Scottish National Antarctic Expedition of 1902–04, who had harboured plans for an Antarctic crossing since 1908, but had abandoned the project for lack of funds. Bruce generously allowed Shackleton to adopt his plans,
 although the eventual scheme announced by Shackleton owed little to Bruce. On 29 December 1913, having acquired his first promises of financial backing—a £10,000 grant from the British Government—Shackleton made his plans public, in a letter to
Map published in March 1916, indicating the planned course of the expedition.
Shackleton called his new expedition the Imperial Trans-Antarctic Expedition, because he felt that "not only the people of these islands, but our kinsmen in all the lands under the
Union Jack will be willing to assist towards the carrying out of the ... programme of exploration."
 To arouse the interest of the general public, Shackleton issued a detailed programme early in 1914. The expedition was to consist of two parties and two ships. The Weddell Sea party would travel in the
Endurance and continue to the Vahsel Bay area, where fourteen men would land of whom six, under Shackleton, would form the Transcontinental Party. This group, with 69 dogs, two motor sledges, and equipment "embodying everything that the experience of the leader and his expert advisers can suggest",
 would undertake the 1,800-mile (2,900 km) journey to the Ross Sea. The remaining eight shore party members would carry out scientific work, three going to
Graham Land, three to
Enderby Land and two remaining at base camp.
Ross Sea party would set up its base in McMurdo Sound, on the opposite side of the continent. After landing they would lay depots on the route of the transcontinental party as far as the
Beardmore Glacier, hopefully meeting that party there and assisting it home. They would also make geological and other observations.
Corporate sponsorship for the expedition;
is loaded with paraffin provided by
Shackleton estimated that he would need £50,000 (current value £4,404,000) to carry out the simplest version of his plan.
 He did not believe in appeals to the public: "(they) cause endless book-keeping worries".
 His chosen method of fund-raising was to solicit contributions from wealthy backers, and he had begun this process early in 1913, with little initial success.
 The first significant encouragement came in December 1913, when the Government offered him £10,000, provided he could raise an equivalent amount from private sources.
Royal Geographical Society, from which he had expected nothing, gave him £1,000—according to Huntford, Shackleton, in a grand gesture, advised them that he would only need to take up half of this sum.
 Lord Rosebery, who had previously expressed his lack of interest in polar expeditions, gave £50.
 In February 1914 The New York Times reported that playwright
J. M. Barrie – a close friend of Captain Scott – had confidentially donated $50,000 (about £10,000).
 With time running out, contributions were eventually secured during the spring and early summer of 1914.
Dudley Docker of the
Birmingham Small Arms Company (BSA) gave £10,000, wealthy tobacco heiress
Janet Stancomb-Wills gave a "generous" sum (the amount was not revealed),
 and, in June, Scottish industrialist
Sir James Caird donated £24,000 (current value £2,110,000). Shackleton informed the
Morning Post that "this magnificent gift relieves me of all anxiety".
Shackleton now had the money to proceed. He acquired, for £14,000 (current value £1,230,000),
 a 300-ton
barquentine called Polaris, which had been built for the Belgian explorer
Adrien de Gerlache for an expedition to
Spitsbergen. This scheme had collapsed and the ship became available.
 Shackleton changed her name to
Endurance, reflecting his family motto "By endurance we conquer".
 For a further £3,200 (current value £282,000), he acquired
Douglas Mawson's expedition ship
Aurora, which was lying in
Tasmania. This would act as the Ross Sea party's vessel.
How much money Shackleton raised to meet the total costs of the expedition (later estimated by the Daily Mail to be around £80,000,
 is uncertain, since the size of the Stancomb-Wills donation is not known. Money was a constant problem for Shackleton, who as an economy measure halved the funding allocated to the Ross Sea party, a fact which the party's commander
Aeneas Mackintosh only discovered when he arrived in Australia to take up his duties.
 Mackintosh was forced to haggle and plead for money and supplies to make his part of the expedition viable.
 Shackleton had, however, realised the revenue-earning potential of the expedition. He sold the exclusive newspaper rights to the
Daily Chronicle, and formed the Imperial Trans Antarctic Film Syndicate to take advantage of the film rights.