La Fayette Sabine Foster[note 1] (November 22, 1806 – September 19, 1880) was an American politician and jurist from Connecticut.

He was President pro tempore of the United States from 1865 to 1867, and was first in the presidential line of succession for most of his tenure, following the assassination of Abraham Lincoln.

Cornelius B. Everest of Windham, Connecticut, in 1824, and in February 1825 enrolled at Brown University in Providence, Rhode Island.

He opened a law office in Hampton, Connecticut in 1833, but then moved back to Norwich a year later, which became his home for the rest of his life.

Foster was the editor of the Norwich Republican, a Whig newspaper, and relinquished the position after his legal business greatly increased.

[2]: 8, 9 In 1846, Foster took his first journey to Europe, sailing for Liverpool on the packet ship Henry Clay, under captain Ezra Nye, on October 7, 1846.

In 1848, he was considered by the Whig Party in the United States Senate elections of that year and received several votes in the nomination, but was ultimately unsuccessful.

[2]: 12 [5] Foster was appointed as the State Director for the Merchants' Bank, Norwich, for the year after he was nominated by Philo M. Judson and a successful vote.

On May 19, 1854, Foster was elected to a full six-year term in the United States Senate by the votes of the Whigs and Free Soilers.

[2]: 11, 13 Foster's first notable speech in the Senate was given on June 25, 1856, in which he eulogized and defended the participants of a public meeting in New Haven to extend aid to departing emigrant Free-Staters, and analyzed the arguments of Stephen A. Douglas, the author of the Kansas–Nebraska Act.

In 1858, during the deliberations regarding the admission of the state of Kansas under the proposed Lecompton Constitution, he said the repeal of the Missouri Compromise "was a violation of plighted faith.

Buchanan's message included a recommendation that he be authorized "to employ a sufficient military force to enter Mexico, for the purpose of obtaining indemnity for the past and security for the future."

Foster opposed Buchanan's recommendation in a speech condemning it as unconstitutional, against international law, and with intent to conquest Mexico, which he considered undesirable for many reasons.

He referred to the advertisements in Southern journals setting prices on the heads of Northern abolitionists, to the outrages committed by the polygamist Mormons in the Utah Territory,[note 2] and to the bad faith of the U.S. government to the Native Americans.

Foster sought reelection to a third term in 1866, but was defeated by Orris S. Ferry; his Senate career ended on March 3, 1867.