Elizabeth Longford,

96, the best-selling biographer and political activist who was the widow of the social reformer Lord Longford and the matriarch of a family that bred other well-known writers, died Wednesday at her home in Sussex.

From her school years through the nearly seven decades of her marriage to Lord Longford, she was famous for her intelligence, beauty, vitality and vivacity.

She was already an academic and social success at Oxford University when John Betjeman, one of the many literary figures she befriended, called her "the aesthetes' moll." Quintin Hogg, who later as Lord Hailsham became a Conservative lord chancellor, said, "There was not an undergraduate who would not consider it a privilege to hold an umbrella over her."

Among her seven surviving children are the writers Antonia Fraser, Rachel Billington and Thomas Pakenham and the poet Judith Kazantzis. A daughter, Catherine, a magazine writer, died in a car crash in 1969 at age 23. A prominent prize for women in journalism is named for her.