David H. Souter, a New Hampshire Republican who was named to the Supreme Court by President George H.W. Bush and who over 19 years on that bench became a mainstay of the court’s shrinking liberal wing, died on Thursday at his home in Concord, N.H. He was 85.

His death was announced on Friday morning by the Supreme Court, which did not cite a cause, saying only that he had died “peacefully.”

A shy man who never married and who much preferred an evening alone with a good book to a night in the company of Washington insiders, Justice Souter retired at the unusually young age of 69 to return to his beloved home state. His retirement at the end of the court’s 2008-2009 term gave President Barack Obama a Supreme Court vacancy in the opening months of his presidency. The president named Judge Sonia Sotomayor to the seat.

By the end of his second year on the Supreme Court, Justice Souter had acquired the label that would stick for the remainder of his tenure. He was the justice who surprised the president who appointed him; who left conservative Republicans bitterly disappointed; whose migration on the bench from right to left led to the cry of “no more Souters” when another president named Bush, George W., had Supreme Court vacancies to fill.

Those who expressed such surprise, who either implicitly or directly accused Justice Souter of having portrayed himself one way and of turning out to be something else entirely, either failed to pay attention to his testimony before the Senate Judiciary Committee during his confirmation hearing in September 1990, or chose not to believe what they heard.