The Peace Ship was the common name for the ocean liner Oscar II, on which American industrialist Henry Ford organized and launched his 1915 amateur peace mission to Europe; Ford chartered the Oscar II and invited prominent peace activists to join him. He hoped to create enough publicity to prompt the belligerent nations to convene a peace conference and mediate an end to World War I, but the mission was widely mocked by the press, which referred to the Oscar II as the “Ship of Fools” as well as the “Peace Ship”. Infighting between the activists, mockery by the press contingent aboard, and an outbreak of influenza marred the voyage. Four days after Oscar II arrived in Norway, a beleaguered and physically ill Ford abandoned the mission and returned to the United States. The peace mission was unsuccessful, which reinforced Ford’s reputation as a supporter of unusual causes.
In early 1915, Ford began to express pacifist sentiments publicly and to denounce the ongoing war in Europe. Later that year, American peace activist Louis Lochner and Hungarian journalist Rosika Schwimmer approached Ford, now commonly recognized as a pacifist, with a proposal to launch an amateur diplomatic mission to Europe to broker an end to World War I. Schwimmer claimed to possess diplomatic correspondence that proved that the European powers were willing to negotiate, which was an outright fabrication. Nevertheless, Ford agreed to finance a peace campaign.
Ford initially sought President Woodrow Wilson's endorsement of his diplomatic undertaking. Ford and Lochner secured a meeting with Wilson at the White House and proposed for Wilson to commission Ford's mission to Europe officially. Although Wilson was sympathetic to Ford’s aims, he declined the offer on the ground that the venture was most unlikely to succeed.
Disappointed by Wilson's response, Ford told Lochner that Wilson was a "small man."
Ford was undeterred by Wilson's refusal to endorse the expedition and planned it as a private delegation to Europe. On 24 November 1915, he announced to a New York City press conference that he had chartered the ocean liner Oscar II for a diplomatic mission to Europe, and he invited the most prominent pacifists of the age to join him. Among those invited were Jane Addams, William Jennings Bryan, Thomas Edison, and John Wanamaker.