When looking for a wife, in this case queen, "different" criteria were used than those currently used, normally they had to do with political and economic alliances. But the case at hand goes a little further, queen was chosen by name .
In a three-way agreement between Felipe II Augusto (King of France), John I (King of England) and Alphonse VIII (King of Castile) decided to marry the future King of France, Louis VIII, to one of Alfonso's two unmarried daughters. The King of England did not care about one or the other and the French monarch, I suppose thinking of his son, decided to send an "observation" group to choose the most beautiful.
They appeared in Burgos to meet the candidates and check their beauty. Their interrogations focused on the most beautiful and when they asked her name, the princess replied:
Magpie
That name must have sounded very bad in their refined ears and they rejected her. They went to question the other sister and when they asked her name:
White
This name fit more with the future queen of France and she was chosen. In 1200 they got married.
History gave them the reason for the good work of which she was queen consort and regent of France.
Source:The reverse side of history – Pedro Voltes.
Image:Wikipedia (Coronation of Louis VIII and Blanca de Castilla)