Princess Marella Caracciolo di Castagneto

Donna Marella Agnelli (born Marella Caracciolo di Castagneto; born May 4, 1927) is an Italian-American socialite, style icon and wife of Fiat chairman Gianni Agnelli. Agnelli has often appeared in Vogue and was included on the International Best Dressed List in 1963. She was also included on the list's Hall of Fame.

Marella Caracciolo di Castagneto was born in Florence to an old noble Neapolitan family. Her father was Filippo Caracciolo, 8th Principe di Castagneto, 3rd duca di Melito, and a hereditary Patrician of Naples (1903-1965). Her mother was the former Margaret Clarke of Peoria, Illinois. She had one sibling, a brother, Carlo Caracciolo, who inherited their father's titles and founded the newspaper La Repubblica.

She was married to FIAT magnate Gianni Agnelli from 19 November 1953 until his death. They had two children:

Edoardo Agnelli (9 July 1954 - 15 November 2000)

Margherita Agnelli (born 26 October 1955)

The accomplished Agnelli, who was educated in Paris, was an assistant to Erwin Blumenfeld in New York early in her varied career, as well as an occasional editor and photographic contributor to Vogue. In 1973, she created a textile line for Abraham-Zumsteg, for which she was awarded the Resources Council's prestigious 'Roscoe' (the design trade's equivalent of the Oscar) in 1977. An avid gardener, Agnelli has authored a number of books on the subject, also providing many of the photographs. Two of her books is about the Garden of Ninfa (1999) and The Agnelli Gardens at Villar Perosa (1998).

More recently, she oversaw the opening of the Renzo Piano-designed art gallery, Pinacoteca Giovanni and Marella Agnelli, built on the roof of the famous former Lingotto Fiat factory in Turin, Italy.

The reserved, patrician tastemaker and socialite is also known for her inclusion in Truman Capote's famous circle of 'swans'— wealthy, stylish, and well-married women friends whose company he adored because they 'had created themselves, as he had done,' and 'had stories to tell' (Gerald Clarke, Capote, pp. 274-75). According to Capote, Agnelli was 'the European swan numero uno,' the youngest in a group that included Babe Paley, Gloria Guinness, C. Z. Guest, Slim Keith, and Pamela Harriman, among others. In her autobiography, Washington Post publisher and Capote friend Katharine Graham recounts that the author once told her that if Paley and Agnelli were 'both in Tiffany's window, Marella would be more expensive' (Personal History, p. 393).

She was portrayed in the 2006 film Infamous by Isabella Rossellini.

Marella Caracciolo di Castagneto (later Marella Agnelli; born May 4, 1927) is an Italian-American who made a small but significant name as a furniture designer and a bigger name as a tastemaker in the New York of the 1950s and 1960s. She was one of Truman Capote's so-called "swans" along with Gloria Guinness, Babe Paley and Slim Keith.

Comparing her to fellow swan Babe Paley, Capote remarked

   If they were both in Tiffany's window, Marella would be more expensive.

Marella Caracciolo was born in Florence to a noble family of Neapolitan origin. In 1953 she married the FIAT magnate Gianni Agnelli. Their son, Edoardo Agnelli, was born the next year.

She often appeared in Vogue and was admitted to the International Best Dressed List in 1963 and later entered its Hall of Fame.

She was portrayed in the 2006 film Infamous by Isabella Rossellini.