The author, Anne Chambers, is best known for her biography of Grace, Ireland's Pirate Queen, and is author of the programme notes for the musical.

The first half of Tibbot's biography is more about Grace than it is about her son, which might partly explain the Shadow Lord title, though that could also be because he operated with two faces in the shadows cast between the old Ireland and the new Anglo Ireland.

Granuaile was not a queen at all, and many would argue not a real pirate either, in the way that Sir Francis Drake, for example, was a real pirate. But a feminist heroine she is and Queen Elizabeth I of England, surrounded as she was by bossy men on all sides, was so keen to talk to Grace when she sailed into London to plead for her son Tibbot that she, Lizzie, actually learnt to speak some Irish in preparation. While there, Grace witnessed at first hand the united English front in operation, got ideas about rethinking strategy, made promises to the crown, handed over Tibbot's nine-year-old son Miles as a pledge of loyalty, and sailed back home where she and her family began to settle old scores in preparation for keeping power in an Ireland where creeping Anglicisation was wiping out the ancient Brehon laws, under which leaders were elected, not automatically entitled to lordships by primogeniture.

Fear, famine, pestilence and finally dispossession ruled the land and by the end of the Nine Years' War, with the O'Neill and O'Donnell clans routed, Tibbot, who stayed happily married to Maeve O'Connor Sligo in a time when multiple marriages, divorce and concubinage were the norm, continued to use both sets of laws to his advantage, choosing survival over idealism even at the expense of his kin, and going on to become fabulously rich with at least a dozen castles, islands and countless acres of land.

But, though he accepted a knighthood and became Viscount Mayo, Chambers says he never totally abandoned the Gaelic cause until his death in 1629, where tradition (disputed) says he was stabbed by his brother-in-law on a journey to the Abbey of Ballintubber.

This book is a big, very detailed miscellany of facts. Competent from an historical point of view, often it is only bald facts, rather than a compelling narrative, and can be exasperating with its endless sequences of alliances and agreements. You don't readily get a sense of the texture of real life as lived, though there is a colourful and vivid description of one of the last massed clan gatherings on a wide limestone plateau in Co Mayo, and another one of Dublin city in the early 17th century.

Tibbot-de-long (Tibbot of the boats, because he was born aboard one of his mother's galleons) and his contemporaries rarely come fully to life as personalities on these pages. We must look to a poet of the time, quoted by Chambers in translation, for that: "Tiboid a burc of the valiant feats/ Of the hawklike blue eye/ He is the warrior of the curving neck/ With ringleted golden-yellow hair/ Is secretly loved by girls in every region."