During nearly two decades as chief justice of the United States, William Rehnquist presided over an increasingly conservative Supreme Court.
Chief Justice Rehnquist: Witty, erudite and conservative
William Hubbs Rehnquist was born in 1924 in a staunchly Republican area of Milwaukee, Wisconsin, into a well-to-do family.
Even as a child, he expressed a desire to make his mark, telling one of his teachers that his career plan was to "change the world".
During World War II he served as a volunteer civil defence officer before joining the Army Air Corps.
An extremely bright student, William Rehnquist earned degrees from both Stanford and Harvard universities before graduating top of his class at Stanford Law School in 1952.
The same year, he began his legal career, serving for 18 months as a clerk to Supreme Court Justice Robert Jackson, who had been the chief US prosecutor at the Nuremberg war crimes trials.
From Jackson, he took his favourite quote, one which followed him down the years: "We must never forget that the record on which we judge these defendants today is the record in which history will judge us tomorrow."
Rehnquist went on to serve as an assistant attorney general at the US Department of Justice, while also playing an active role in Republican politics.
His reward finally came in 1971, when that arch-Republican, President Richard Nixon, nominated Rehnquist to the Supreme Court.
Richard Nixon nominated Rehnquist for the Supreme Court in 1972
During his time at the court, which he would head after being nominated to be the 16th chief justice by Ronald Reagan in 1986, William Rehnquist presided over a conservative transformation of what is arguably the most powerful institution in the United States.
Rehnquist's gut instincts - pro-states' rights, anti-big government and anti- affirmative action - informed his legal opinions.
He did not win every argument - voting, for instance, against the legalisation of abortion as an associate justice in 1973 - but his conservative world-view often prevailed as successive Republican appointees subtly shifted the Supreme Court to the right.
'A wiser man'
The political role of the chief justice is not confined to administering the oath of office at presidential inaugurations and, in recent years, Rehnquist found himself presiding over a number of controversial cases.
In 1988, he had voted in favour of the creation of an independent counsel, a senior prosecutor separate from the Department of Justice, charged with investigating alleged crimes at the very highest level.
And during the 1990s, special prosecutor Kenneth Starr twice investigated President Bill Clinton, over Whitewater and Monica Lewinsky. When the second case led to President Clinton's impeachment by the US Senate, it was Chief Justice Rehnquist who presided.
After President Clinton's acquittal, Rehnquist reflected to senators: "I underwent the sort of culture shock that naturally occurs when one moves from the very structured environment of the Supreme Court, to what I shall call, for the want of a better phrase, the more free-form environment of the Senate.
Rehnquist presided over Bush's inauguration in January 2005
"I leave you now a wiser, but not a sadder, man."
Following the disputed presidential election of 2000, Rehnquist presided over the high court hearing which decided that there would be no second recount in Florida, thereby handing the White House to George W Bush.
While Rehnquist often presented a solemn and austere figure, behind the scenes, he was described by colleagues as a down-to-earth person with a good sense of humour.
William Rehnquist was diagnosed with thyroid cancer last autumn. At the start of 2005, and with the help of a walking stick, he presided over George W Bush's second inauguration, and administered the oath of office as usual.