Mr.
Sumner's labor was given almost exclusively to questions involving our foreign relations, and to issues growing out of the slavery agitation.

To the latter he devoted himself, not merely with unswerving fidelity but with all the power and ardor of his nature.
Upon general questions of business in the Senate he was not an authority, and rarely participated in the debates which settled them; but he did more than any other man to promote the anti-slavery cause, and to uprear its standard in the Republican party.

He had earned, in an unexampled degree, the hatred of the South, and this fact had increased the zeal for him among anti-slavery men throughout the North.

The assault, made upon him by Preston S.Brooks, a South-Carolina representative, for his famous speech on Kansas, had strengthened his hold upon his constituency, which was not merely the State of Massachusetts but the radical and progressive Republicans of the entire country.
Mr.Sumner was studious, learned, and ambitious.

He prepared his discussions of public questions with care, but was not ready as a debater.