Catherine, or Kate as she is known is not an aristocrat.
* She was born on Jan. 9, 1982, into a middle-class family from Berkshire, west of London, the eldest of three children.
* Her father Michael worked as a pilot and her mother Carole as an airline stewardess.
Carole Middleton's maternal family, the Harrisons, were working class labourers and miners from County Durham.
In 1987, the Middletons founded their own company, Party Pieces, a mail order firm that sells party supplies and decorations. They have since become millionaires.
* She met Prince William at St Andrews University in Scotland in 2001, where she read history of art. The pair lived together in a house shared with friends.
In November 2006 Middleton accepted a position as an assistant accessories buyer with clothing chain Jigsaw.
* They split up in 2007 after William was posted around the country as part of his military training, according to media reports. Since getting back together later that year, there has been persistent talk about a possible engagement.
* Critics in the tabloid press nicknamed Middleton "Waity Katie" after a marriage date failed to materialise and accused her of doing little with her life beyond waiting for William to pop the question.
* Middleton's lawyers complained to Britain's press watchdog in 2007 after photographers and TV film crews mobbed her outside her London flat, drawing comparisons with the media's obsession with William's mother, the late Princess Diana -- who died in a Paris car accident while being pursued by paparazzi.
As the wife of a royal duke and prince, Kate would assume the courtesy title of Duchess as well as the style of Her Royal Highness.