14th of August, to be precise...from the Aljubarrota battle between Portugal, with English support, against Castilla, with French support. Another cavalry charge against infanty which had time to dig surprises...and archers to take the advantage of the confusion.

Made of Cotton and silk, and decorated with the shield of the king, it was preserved as a national relic until today. It's shown in the Alberto Sampaio Museum:

http://masampaio.imc-ip.pt/pt-PT/colec/textil...spx?id=330
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More pictures here

I'm surprised of not having found nothing here, as even there is a book in Portuguese and English about it...

http://www.ipmuseus.pt/pt-PT/recursos/publica...spx?id=661[b]
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