Brown spokesman Steven Glazer said 2,300 people were invited to Monday's inauguration, with 700 other tickets handed out to members of the public.
Brown, who was governor from 1975 to 1983, is the first California governor to serve non-consecutive terms and the second to serve a third term. Earl Warren, who governed from 1943 to 1953, was elected three times but left in the middle of his final term when he was appointed chief justice of the United States by President Eisenhower.
Though the spotlight Monday was on Brown, several other state officials were also sworn in, with less fanfare.
They included newly elected Atty. Gen. Kamala Harris, Insurance Commissioner Dave Jones and Superintendent of Public Instruction Tom Torlakson. State Treasurer Bill Lockyer, Secretary of State Debra Bowen and Controller John Chiang began their second terms Monday.
Lt. Gov.-elect and San Francisco Mayor Gavin Newsom delayed his swearing-in by a week, until Jan. 10. He is staying on as mayor for an extra week to allow the newly elected San Francisco Board of Supervisors to take office before he leaves. The new board, which is seen as more friendly to Newsom than the current one, will then pick an interim mayor to succeed Newsom.