William III (1689-1702) & Mary II (1689-94) (Britain's only ever 'joint monarchs') 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' wonderful 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.

William III (1689-1702) & Mary II (1689-94) (Britain's only ever 'joint monarchs') 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' wonderful 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.

Foremost medieval historian Anne Curry offers a new reinterpretation of Henry V and the battle that defined his kingship: Agincourt Henry V's invasion of France, in August 1415, represented a huge gamble. As heir to the throne, he had been a failure, cast into the political wilderness amid rumours that he planned to depose his father. Despite a complete change of character as king - founding monasteries, persecuting heretics, and enforcing the law to its extremes - little had gone right since. He was insecure in his kingdom, his reputation low. On the eve of his departure for France, he uncovered a plot by some of his closest associates to remove him from power. Agincourt was a battle that Henry should not have won - but he did, and the rest is history. Within five years, he was heir to the throne of France. In this vivid new interpretation, Anne Curry explores how Henry's hyperactive efforts to expunge his past failures, and his experience of crisis - which threatened to ruin everything he had struggled to achieve - defined his kingship, and how his astonishing success at Agincourt transformed his standing in the eyes of his contemporaries, and of all generations to come.

'After my death,' George V said of his eldest son and heir, 'the boy will ruin himself within twelve months.' The forecast proved uncannily accurate. Edward VIII came to the throne in January 1936, provoked a constitutional crisis by his determination to marry the American divorcée Wallis Simpson, and abdicated in December. He was never crowned king. In choosing the woman he loved over his royal birthright, Edward shook the monarchy to its foundations. Given the new title 'Duke of Windsor' and essentially sent into exile, he remained a visible skeleton in the royal cupboard until his death in 1972 and he haunts the house of Windsor to this day. Drawing on unpublished material, notably correspondence with his most loyal (though much tried) supporter Winston Churchill, Piers Brendon's superb biography traces Edward's tumultuous public and private life from bright young prince to troubled sovereign, from wartime colonial governor to sad but glittering expatriate. With pace and panache, it cuts through the myths that still surround this most controversial of modern British monarchs.

On Christmas Day 1066, William, duke of Normandy was crowned in Westminster, the first Norman king of England. It was a disaster: soldiers outside, thinking shouts of acclamation were treachery, torched the surrounding buildings. To later chroniclers, it was an omen of the catastrophes to come. During the reign of William the Conqueror, England experienced greater and more seismic change than at any point before or since. Marc Morris's concise and gripping biography sifts through the sources of the time to give a fresh view of the man who changed England more than any other, as old ruling elites were swept away, enemies at home and abroad (including those in his closest family) were crushed, swathes of the country were devastated and the map of the nation itself was redrawn, giving greater power than ever to the king. When, towards the end of his reign, William undertook a great survey of his new lands, his subjects compared it to the last judgement of God, the Domesday Book. England had been transformed forever.

The elder daughter of Henry VIII, Mary I (1553-58) became England's ruler on the unexpected death of her brother Edward VI. Her short reign is one of the great potential turning points in the country's history. As a convinced Catholic and the wife of Philip II, king of Spain and the most powerful of all European monarchs, Mary could have completely changed her country's orbit, making it a province of the Habsburg Empire and obedient again to Rome. These extraordinary possibilities are fully dramatized in John Edward's superb short biography. The real Mary I has almost disappeared under the great mass of Protestant propaganda that buried her reputation during her younger sister, Elizabeth I's reign. But what if she had succeeded?

King John ruled England for seventeen and a half years, yet his entire reign is usually reduced to one image: of the villainous monarch outmanoeuvred by rebellious barons into agreeing to Magna Carta at Runnymede in 1215. Ever since, John has come to be seen as an archetypal tyrant. But how evil was he? In this perceptive short account, Nicholas Vincent unpicks John's life through his deeds and his personality. The youngest of four brothers, overlooked and given a distinctly unroyal name, John seemed doomed to failure. As king, he was reputedly cruel and treacherous, pursuing his own interests at the expense of his country, losing the continental empire bequeathed to him by his father Henry and his brother Richard and eventually plunging England into civil war. Only his lordship of Ireland showed some success. Yet, as this fascinating biography asks, were his crimes necessarily greater than those of his ancestors - or was he judged more harshly because, ultimately, he failed as a warlord?

A major new title in the Penguin Monarchs series In his fascinating new book in the Penguin Monarchs series, Richard Abels examines the long and troubled reign of Aethelred II the 'Unraed', the 'Ill-Advised'. It is characteristic of Aethelred's reign that its greatest surviving work of literature, the poem The Battle of Maldon, should be a record of heroic defeat. Perhaps no ruler could have stemmed the encroachment of wave upon wave of Viking raiders, but Aethelred will always be associated with that failure. Richard Abels is Professor Emeritus at the United States Naval Academy. He is the author of Alfred the Great: War, Kingship and Culture in Anglo-Saxon England and Lordship and Military Obligation in Anglo-Saxon England. He is a Fellow of the Royal Historical Society.

William IV, the 'Sailor King', reigned for just seven years. Rash and impetuous as a young man, he was sent to join the navy by his father, George III, to bring him to order, but he was overpromoted at an early age and saw his years of active service marked by a series of calamities. He was also notorious for his mounting debts and his long relationship with the actress Mrs Jordan, with whom he had ten children. Yet, as Roger Knight, one of Britain's foremost naval historians, shows in this concise and perceptive biography, William's bluff, unpolished sailor's manner made him popular with the people. Inheriting the throne amid strikes, riots and the push for parliamentary reform, he helped see the country through the great constitutional crisis of the era. Despite his many flaws, he was perhaps a better king than sailor, leaving the monarchy in a healthier state than when he found it, and enabling the smooth succession of his niece, Victoria.

The elder daughter of Henry VIII, Mary I (1553-58) became England's ruler on the unexpected death of her brother Edward VI. Her short reign is one of the great potential turning points in the country's history. As a convinced Catholic and the wife of Philip II, king of Spain and the most powerful of all European monarchs, Mary could have completely changed her country's orbit, making it a province of the Habsburg Empire and obedient again to Rome. These extraordinary possibilities are fully dramatized in John Edward's superb short biography. The real Mary I has almost disappeared under the great mass of Protestant propaganda that buried her reputation during her younger sister, Elizabeth I's reign. But what if she had succeeded?