Bonaventure of Siena

He arrived after Alfonso's election as Holy Roman emperor, along with may other expatriates from the Ghibelline city of Siena.

[2] On 10 May 1266, on Alfonso X's instruction, he drew up the act by which the infante Fernando de la Cerda named the men who would represent him at his proxy marriage to Blanche, daughter of Louis IX of France.

[3] On 18 January 1284, Peter III of Aragon named a certain Filippo Bonaventura da Siena, recommended to him by Cardinal Latino Malabranca Orsini, as a member of his familia regis.

[1] His presence in Spain would be explained by his father's earlier contacts there, although the exact purpose of his visit is unknown.

[4] Bonaventure was commissioned by Alfonso X to translate the Book of Muhammad's Ladder into Latin and possibly also French.