1756: President's (Maclean) House
Photograph after remodeling of 1868
Source: Unknown
View from the north
Source: RJC?
Plan of ground floor
Source: Savage, Nassau Hall, 1756-1956, p.22
Reconstruction perspective of view from Nassau Hall as of 1756
Source: Princeton Alumni Weekly, v.52 (10/5/51), p.7
John Maclean House, originally the President's House, shares with Nassau Hall the honor of seniority among University buildings; both are accorded the same date of construction (1756) in official records, although it is probable that the President's House was not ready for occupancy until several months after Nassau Hall. Designed and built by Robert Smith, co-architect and builder of Nassau Hall, it was occupied by ten presidents of the College -- Burr, Edwards, Davies, Finley, Witherspoon, Smith, Green, Carnahan, Maclean, and McCosh -- until Prospect was acquired as the President's residence in 1878. After President McCosh moved into Prospect, James Ormsbee Murray, Professor of English, occupied the old President's House and continued to live there after his appointment to the new office of dean of the faculty in 1883. Thereafter until 1967 it was the residence of the first seven deans of the faculty -- Murray, Winans, Fine, Magie, Eisenhart, Root, and Brown -- and was called the Dean's House. In 1968, when it became the home of the Alumni Council, it was renamed in honor of John Maclean, Jr., founder of the Alumni Association and the last president to occupy the house throughout his administration; "when he was president," John F. Hageman, historian of the Princeton community wrote in 1878,"he kept his mansion filled with guests as if it were a public house."
President's House in the Campus Evolution narrative
Anecdotes and legends of President's House may be found here.
Source: Leitch, p. 299
More information on President's House
Wikipedia article