What color Charlene chooses to wear during her state visit alongside Prince Albert II next week has major significance as she is one of seven women in the world that has been given "the privilege of the white" – or the ability to wear white when meeting with the pope.
Called le privilége du blanc in French or il privilegio del biacno in Italian, the special tradition is extended solely to designated Catholic queens and princesses and is usually reserved for important events at the Vatican like private audiences, canonizations, beatifications and special masses. According to protocol, other women who meet with the pope are asked to wear black clothes and a matching mantilla, or a lace veil worn over the head. First Lady Michelle Obama followed this rule in 2009 when she joined President Barack Obama in visiting Pope Benedict XVI.
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It is also not given to every Catholic monarch's wife as Princess Marie of Liechtenstein and Queen 'Masenate Mohato Seeiso of Lesotho apparently do not have the privilege. The women traditionally need to be the queens of a "Most Catholic Majesty" or Rex Catholicissimus – either as consort or in their own right as regnant – a title given to Catholic monarchs by the pope and is considered hereditary unless taken away by the pontiff.
Charlene, who converted to Catholicism ahead of her 2011 wedding to Albert, has exercised the privilege once before when she met with Pope Benedict XVI at the Vatican in January 2013. Her appearance caused a stir amongst royal watchers as the monarchs of Monaco are not traditionally considered to be in the Most Catholic Majesties (hence why the royal families of Lichtenstein and Lesotho are not given the privilege of the white). However, the Vatican's press office confirmed after the meeting in 2013 that Charlene had been given the privilege of the white – making her the first consort from Monaco to have been included in the special club.
The privilege of the white has even resulted in a minor political snafu. Back in April 2006, Cherie Blair, the wife of former British Prime Minister Tony Blair and an observant Catholic, wore white when she met with Pope John Paul II at the Vatican. Blair's decision to wear white – even though she wasn't the wife of a Catholic monarch – raised eyebrows and even drew condemnation from a Catholic British MP who accused her of having "a very grand idea of herself."
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