Judge William Wardwell Treat, 91, died Jan. 10, 2010, at Naples Community Hospital following a heart attack. He was a retired diplomat, banker and judge, also of Stratham, N.H.

He was born May 23, 1918, to Joshua and Clara (Atwood) Treat of Winterport.

He was appointed by President Ronald Reagan in 1987 and in 1990 by President George H.W. Bush as a public delegate to the General Assembly of the United Nations, where he focused on international human rights.

In 1988 he was elected by the United Nations Human Rights Commission as the United States member of the Sub-Commission on Prevention of Discrimination and Protection of Minorities at the U.N. Human Rights Centre in Geneva, Switzerland, for a 4-year term. In 1990 he was named by the Sub-Commission to prepare a study concerning international standards for fair trials and the right to habeas corpus, which was completed in 1994 and approved by the Human Rights Commission in 1995.

Treat was appointed judge of probate in New Hampshire in 1958 and served until his retirement in 1983. He founded the National College of Probate Judges in 1968 and was its first president; it now has more than 600 members. The Treat Award, presented to the judge who has done the most for the improvement of probate law in the United States, includes among its recipients former Supreme Court Justice Sandra Day O’Connor.

In New Hampshire he was chairman of the Judicial Council and the author of a three-volume text on probate law, Treat on Probate. He was the first chairman of the Administrative Committee for District and Municipal Courts and the author of a study, which resulted in a reorganization and consolidation of the local court system in New Hampshire.

He was the founder and chairman of Bank Meridian, a national bank with offices in Portsmouth, Exeter, Hampton and other New Hampshire seacoast communities. It was sold in 1985 to Amoskeag Bank Shares of Manchester, N.H.

Treat also served as a director of the Federal Reserve Bank of Boston; was chairman of the Towle Manufacturing Company of Newburyport, Mass., a director of the Colonial Group Inc. of Boston, and of Unitil Inc. of New Hampshire.

Treat was a graduate of the University of Maine and Harvard Graduate School of Business Administration. He received an honorary doctor of laws degree from the University of Maine in 1992 and from the University of New Hampshire in 2001.

In 1991 he received the Silver Shingle Award, the highest alumni award presented by the Law School of Boston University. Plymouth (N.H.) College awarded him the “Granite State Citizen Award” for outstanding citizenship in 1988. He established the Treat Scholarship at the University of Maine for needy students.

Treat was chairman of the New Hampshire Republican Party from 1954 to 1958 and a member of the Republican National Committee from 1960 to 1964. He served as secretary of the United States Electoral College from 1956 to 1964. He was a delegate to the Republican National Conventions in 1956, 1960, 1964 and 1988. He served as chairman of the program committee of the 1964 Republican Convention in San Francisco.

Treat was a direct descendant of Gov. Robert Treat, colonial governor of Connecticut for 40 years, and a collateral descendant of Robert Treat Paine, a signer of the Declaration of Independence. He was a member of the Society of the Cincinnati, the Society of Mayflower Descendants, and a former governor of the Society of Colonial Wars. He was also a governor of the American Independence Museum in Exeter, N.H., and a trustee of Franklin Pierce College in Rindge, N.H.

He established the Treat Foundation, a family charitable trust devoted to various charitable purposes, and he was also a member of the Tavern Club, the Union Club and the Harvard Club, all of Boston.

He was the husband of the former Vivian S. Baker of Providence, R.I., and the father of Jonathan B. Treat II of Belmont, Mass., and Mary Esther C. Treat of Burlington, Vt. He was the grandfather of Elizabeth Treat Stetson and Hilary Thompson Treat of Washington, D.C., and Joshua Atwood Treat of Belmont, Mass. He is also survived by a sister-in-law, Virginia Vannah Treat, of Belfast; a niece, Nancy Treat Burnham, and a nephew, Donald (“Chip”) Clark, of Searsport; and a nephew, Joshua Treat IV, and a niece, Anne Clark Treat, both of Belfast.

Treat was predeceased by a brother, Joshua Treat in 2009 ;a sister, Mary Esther Treat Clark, in 2005; and a niece, Linda Treat Olsen, in 2000.

A memorial service will be held at Phillips Chapel, Exeter, N.H., June 13, at 2 p.m.

In lieu of flowers the family suggests contributions to the William Treat Scholarship Fund of the Treat Foundation (c/o Ms Joey Stroble, P.O. Box 800, Stratham, NH 03885).

Interment at the Oak Hill Cemetery in Winterport will be at a date to be determined later.

For online condolences visit fullerfuneralhome.com