This book seeks to explain the importance of Wales in the Wars of the Roses which, the author argues, has never been given the prominence it deserves. From the landing of Richard Duke of York at Denbigh in September 1450 to the death of his youngest son and namesake, Richard III at Bosworth in 1485 Wales and its resources were central to the conflict. Wales and the Marches provided the strength for Richard Duke of York, calling upon the old Mortimer retinue, to challenge the rule of Henry VI, not only in 1450 but again in 1452 and 1455. In opposition to York's presumption, Both Edmund and Jasper Tudor were sent to their homeland in Wales in 1456, initiating 30 years of blood-feud.

Welshmen fought at Mortimer's Cross and the Marchmen made Edward IV king and provided the army who fought for him at Towton in 1461. Welshmen also supported Jasper as Earl of Pembroke and through the years that led to the triumph at Bosworth. Henry VII was born at Pembroke, where he was welcomed back in 1485.

The book examines the intense rivalry between the Houses of Lancaster and York as they battled for the loyalties of the men of Wales and the Marches. The intense familial rivalry, generational blood feuds and hatred bred the fratricidal violence that led to the Tudor triumph and paved the way for Henry VIII's Acts of Union.