In January, 1868, he was solicited to take the office of president of the New England Historic Genealogical Society, vacated by the death of Governor Andrew. He was unanimously elected, and is now serving the seventeenth year of his presidency. At every annual meeting he has delivered an appropriate address. In his first address he urged the importance of procuring a suitable building for the society. In 1870, he said: "The time has now arrived when absolute necessity, public sentiment, and personal obligations, demand that this work be done, and done quickly." Feeling himself pledged by this address, he, as chairman of the committee then appointed, devoted three months entirely to the object of soliciting funds, during which time more than forty thousand dollars was generously contributed by friends of the association; and thus the handsome edifice at No. 18 Somerset Street was procured. This building was dedicated to the use of the society, March 18, 1871. He has since obtained donations, amounting to upward of twelve thousand dollars, as a fund for paying the salary of the librarian. In 1859, he presided at the first public meeting called in Boston, in regard to the collocation of institutions on the Back Bay lands, where the splendid edifices of the Boston Society of Natural History and the Massachusetts Institute of Technology now stand. Of the latter institution he has been a vice-president, and the chairman of its Society of Arts, and a director from the beginning. General Francis A. Walker, the present president of the Institute, bore this testimony to his efforts in its behalf at the in banquet to Mr. Wilder on his eighty-fifth anniversary: "Through all the early efforts to attract the attention of the legislature and the people to the importance of industrial and art education, and through the severe struggles which so painfully tried the courage and the faith even of those who most strongly and ardently believed in the mission of the Institute, as well as through the happier years of fruition, while the efforts put forth in the days of darkness and despondency were bearing their harvest of success and fame, Colonel Wilder was through all one of the most constant of the members of the government in his attendance; one of the most hopeful in his views of the future of the school; ever a wise counsellor and a steadfast ally." He was one of the twelve representative men appointed to receive the Prince of Wales in 1860, at the banquet given him in Boston, Edward Everett being chairman of the committee; also one of the commissioners in behalf of the Universal Exposition in Paris, 1867, when he was placed at the head of the committee on horticulture and the cultivation and products of the vine, the report of which was published by act of Congress.