The Eagle and the Hart — Helen Castor

Castor sets Richard II and Henry IV alongside each other, tracing the personalities and political pressures that turned two cousins into enemies and produced the first successful deposition of an English king since Edward II. The book is interested in what medieval kingship actually required — the performance of authority, the management of magnates, the limits of royal prerogative — and in how both men misread those requirements, in different ways and with different consequences.