After January 1887, a series of Round Table Conferences took place between Chamberlain, Trevelyan, Harcourt, Morley and Lord Herschell, in which the participants sought an agreement about the Liberal Party's Irish policy. Chamberlain hoped that an accord would enable him to claim the future leadership of the party and that he would gain influence over the Conservatives simply from the negotiations occurring. Although a preliminary agreement was made concerning land purchase, Gladstone was unwilling to compromise further, and negotiations ended by March. In August 1887, Lord Salisbury invited Chamberlain to lead the British delegation in a Joint Commission to resolve a fisheries dispute between the United States and Newfoundland. The visit to the USA renewed his enthusiasm for politics, and enhanced his standing with respect to Gladstone. In November, Chamberlain met 23-year-old Mary Endicott, the daughter of President Grover Cleveland's Secretary of War, William C. Endicott, at a reception in the British legation. Before he left the United States in March 1888, Chamberlain proposed to Mary, describing her as 'one of the brightest and most intelligent girls I have yet met'. In November 1888, Chamberlain married Mary in Washington, D.C., wearing white violets, rather than his trademark orchid. Mary became a faithful supporter of his political ambitions.