Charles Carroll was born in 1737 in Annapolis, Maryland. Until the age of eleven, he was educated by Jesuits, and he later traveled to London and Paris where he studied liberal arts and civil law. Back home in 1765, he built a home on a ten-thousand acre estate given to him by his father, and spent the next ten years or so of his life in relative seclusion. He became increasingly involved in politics starting in 1773, however, when he attended the first Maryland Revolutionary Convention. Between 1774 and 1776 he was a strong supporter of non-importation measures.
In 1776, he and his cousin, a priest, (chosen for their linguistic and religious backgrounds) were part of a failed mission made by Benjamin Franklin and Maryland delegate, Samuel Chase, to establish a union with Canada When he and Chase returned to Philadelphia on June 11, they learned that the vote on Richard Henry Lee's independence resolution had just been postponed, and that Maryland had refused to commit herself. The two, along with another Maryland native, William Paca, headed back to their home state to work for approval of the resolution. When they returned to vote on July 1, they brought Maryland's support of the resolution with them. Three days after the vote, Carroll became a delegate, a position he held until 1778. He was the only Catholic to sign the Declaration of Independence.
Some years later, in 1787, he was elected to, but did not attend the Constitutional Convention. He was a supporter of the Federalists, though, and was responsible, in part, for getting the Constitution ratified in Maryland. Between 1789 and 1792, he served as one of Maryland's first two senators in Congress. In 1804, at the age of sixty-seven, after failing to win a second term in Congress, he retired from politics in order to concentrate on personal affairs.
Carroll was the nation's last surviving signer of the Declaration of Independence, and the longest lived as well. He died in 1832 at the age of ninety-five, and was buried in Doughoregan Manor at the family chapel.