William III (1689-1702) and Mary II (1689-94) were Britain's only ever 'joint monarchs. They changed the course of the entire country's history, coming to power through a coup (which involved Mary betraying her own father), reestablishing parliament on a new footing and, through commiting Britain to fighting France, initiating an immensely long period of warfare and colonial expansion. Jonathan Keates' book makes both monarchs vivid, the cold, shrewd 'Dutch' William and the shortlived Mary, whose life and death inspired Purcell to write some of his greatest music.