Wentworth was born January 29, 1877, in Sandwich, New Hampshire, to Paul and Ellen Tilton (Dunklee) Wentworth. Wentworth attended the Holderness School from 1890 to 1896 and Phillips Academy Andover from 1893 to 1896. For his undergraduate career, he attended Dartmouth College, graduating in 1900. He was a member of the Sphinx, a Dartmouth secret society, and Alpha Delta Phi fraternity. Wentworth graduated from Harvard Law School in 1903, and spent most of his professional career with the law firm Choate, Hall & Stewart in Boston.
