In its familiar translations, the Stabat Mater is a favourite hymn of English-speaking Catholics. But what if these versions are not true to the original Latin? What did the author really say? Why did he use a particular poetic style? Who was he anyway? After seven hundred years, these and other questions about this much loved hymn remain unresolved. Probable authors include three Popes, three Saints and one layman who, though he was imprisoned and excommunicated by a Pope, is perhaps the most likely. Jacopone da Todi's fascinating life story includes the tragic death of his wife, his crazed...