Leonard James Farwell (January 5, 1819 – April 11, 1889) was an American politician and public administrator.

On his return, he settled in Dane County, Wisconsin, where he had invested in a great amount of property and owned roughly half the land of the village of Madison, the capitol of the new state.

He defeated his opponent, former Milwaukee Mayor Don A. J. Upham, and led the Whigs to a strong showing in the Wisconsin Assembly elections down-ballot, though they did not capture other statewide offices.

Farwell's success was likely due to his personal popularity and the contributions he had provided to assist recent immigrants arriving in Wisconsin.

He withdrew to his farm on the northern shores of Lake Mendota and took a role in managing the State Hospital for the Insane.

In 1859, he briefly returned to politics when he was elected on the Republican ticket to represent northern Dane County in the Wisconsin State Assembly for the 1860 session.

[2][3] On the night of April 14, 1865, he was a witness, at Ford's Theatre, to the assassination of President Lincoln by John Wilkes Booth.

He wisely presumed that other high officers of the Lincoln administration might also be endangered by the conspiracy and rushed to the Vice President's boarding place, arriving in time to summon additional guards and save Andrew Johnson from the knife of George Atzerodt.

[4] Governor Farwell then proceeded to Secretary William H. Seward's residence but arrived too late to prevent that attack.