 He was appointed a Knight of the Order of the Golden Fleece, number 58, at the 9th Chapter of the order, held in 1456 at The Hague.While travelling from Rome to Mantua, James of Portugal fell ill and died in Florence on August 15, 1459, at the age of twenty-six.He was buried in the basilica of San Miniato al Monte in Florence, the only tomb in that church.