... was not the first American Vice President to resign; that distinction goes to John C. Calhoun, who resigned in 1832 over differences with the President, Andrew Jackson. (Calhoun had originally been elected to serve under John Quincy Adams.)
My wording (naming Agnew as "the first US Vice President to resign in disgrace") comes from history.com.
The charges that led to Agnew's resignation dated back to his time as Chief Executive of Baltimore County – a position to which he was elected in 1961. In 1967 he became Governor of Maryland, and in the following year he was nominated as the Republican vice presidential candidate. During Nixon's successful campaign, Agnew ran on a tough law and order platform, and as vice president he frequently attacked opponents of the Vietnam War and liberals as being disloyal and un–American.
Having been re–elected with Nixon in 1972, Agnew was investigated by the US Attorney for the District of Maryland on suspicion of criminal conspiracy, bribery, extortion and tax fraud. He was found to have taken kickbacks from contractors during his time as Baltimore County Executive and Governor of Maryland. The payments had continued into his time as vice president, but they had nothing to do with the Watergate scandal – in which Agnew was not implicated.
In October 1973, after months of maintaining his innocence, Agnew pleaded "no contest" to a single felony charge of tax evasion, and resigned from office. Nixon replaced him with Gerald Ford, the Republican leader in the House of Representatives.
Less than ten months after Agnew's resignation, Nixon himself resigned under threat of impeachment on three counts: obstructing the administration of justice in the Watergate investigation, violation of the rights of citizens (for example, attempting to use the IRS, FBI and CIA as weapons against his political opponents) and failing to produce items as ordered by the Judiciary Committee. Nixon was succeeded (like Agnew) by Ford, who granted him a pardon in 1974.
Agnew spent the remainder of his life quietly, rarely making public appearances. He wrote a novel and a memoir, in both of which he defended his actions. He died in 1996, aged 77.
© Haydn Thompson 2021