Born in Alburgh, Vermont on New Year's Day 1856, Sweet attended public schools and the University of Nebraska in Lincoln, and was a member of the Phi Delta Theta fraternity.

[3] On April 24, 1889, President Benjamin Harrison gave Sweet a recess appointment as United States Attorney for the Territory of Idaho.

[5] On November 19, 1889, Harrison again gave Sweet a recess appointment, elevating him to associate justice of the Idaho Territorial Supreme Court.

While in Congress from 1890 to 1895, Sweet was a leading advocate of the free and unlimited coinage of silver, which would pour large sums of money into Idaho.

He closely followed Charles Parnell, the Irish agitator in the British Parliament, who managed to force consideration of his proposals by blocking the legislative process there.