Increase Sumner (November 27, 1746 – June 7, 1799) was an American lawyer, jurist, and politician from Massachusetts. He was the fifth governor of Massachusetts, serving from 1797 to 1799. Trained as a lawyer, he served in the provisional government of Massachusetts during the American Revolutionary War, and was elected to the Confederation Congress in 1782. Appointed to the Massachusetts Supreme Judicial Court the same year, he served there as an associate justice until 1797. He was elected governor of Massachusetts three times by wide margins, but died shortly after the start of his third term. His descendants include his son William H. Sumner, for whom the Sumner Tunnel in Boston, Massachusetts, is named, and 20th-century diplomats Sumner Welles and Sumner Gerard. Early life Increase Sumner was born on November 27, 1746, in Roxbury, Province of Massachusetts Bay, one of eight children of Increase Sumner and Sarah Sharp. The elder Increase Sumner was a successful farmer descended from early settlers of Dorchester; he held a number of public offices including coroner for Suffolk County, and selectman of Roxbury. In 1752 Sumner enrolled in the grammar school in Roxbury, now Roxbury Latin School, where the headmaster was William Cushing, future justice of the Supreme Court of the United States. Sumner excelled at school, and over the resistance of his father (who envisioned his son's future to be in agriculture) was enrolled at Harvard College in 1763. He graduated in 1767. Legal career After graduating from Harvard, Sumner took charge of the Roxbury school, where he taught for two years while he apprenticed law under Samuel Quincy, the provincial solicitor general. He sought to study under John Adams, but the latter had enough students. Adams wrote that Sumner "was a promising genius, and a studious and virtuous youth." Sumner was admitted to the bar in 1770 and opened a law office in Roxbury that year. Sumner was chosen a member of the Massachusetts Provincial Congress in 1776 where he represented the town of Roxbury. In 1777 he participated in a state convention to draft a new constitution, whose result was not adopted. He continued to serve in the provincial congress until the state constitution was adopted in 1780, when he was elected state senator for Suffolk County. This post he held for two years. In June 1782 he was elected to the Confederation Congress by the state legislature, replacing Timothy Danielson, who