Jonathan Ingersoll grew up during the British colonial period. In 1766 he graduated from Yale College. He must have studied law, because he was a judge later. He also embarked on a political career. Between 1792 and 1797 he was a member of the Connecticut Council of Assistants. At that time he joined the Federalist Party. Between 1798 and 1801, and again from 1811 to 1816 he was judge of the Superior Court of his state.
In 1816, Ingersoll was elected to the side of Oliver Wolcott for Lieutenant Governor of Connecticut. This post he held between 1817 and his death in 1823. Yet he was Deputy Governor and Chairman of the State Senate. He was the father of Congressman Ralph Isaacs Ingersoll (1789-1872) and grandfather of Colin M. Ingersoll (1819-1903), who was also a congressman. His younger son, Charles (1798-1860) was a federal judge. Another grandson was Governor Charles Roberts Ingersoll ( 1821-1903 ).