A VERY MOURNFUL BALLAD
ON THE SIEGE AND CONQUEST OF ALHAMA
Lord Byron translated this into English in 1817 and it was first published with the Fourth Canto of Childe Harold's Pilgrimage in 1818.
At the time he submitted it for publication, he requested his publisher to run the Spanish version alongside his translation for comparison and accuracy. I have not seen that particular edition, but the Spanish ballad entitled: Romance de La Perdida de Alhama is much shorter than Byron's translation of twenty-three verses, although the stories are nearly the same.
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