This book begins in 1617, the year that Louis XIII really took power by distancing the queen mother and ordering the assassination of Concini (24 April 1617), and ends in 1648 - five years after the death of Louis XIII - the year of the Westphalia Peace Treaty (24 October 1648). This period was mostly dominated by the personality and works of Richelieu, who entered the king's Council in April 1624. He gave the king an ambition: "to procure the ruin of the Huguenot party, humble the pride of the great, reduce all subjects to their duty, and elevate your majesty's name among foreign nations to its rightful reputation". By the time of his death, on the 4 December 1642, this programme had been accomplished.

The political beliefs of Richelieu gave Louis XIII a powerful instrument that was to emerge transformed from the Thirty Years' War. Commanded by great captains such as the Duc de Rohan, the Viscomte de Turenne and the Prince of Conde, the army was highly successful, as shown by the long list of French victories: Avins and the Valtelline in 1635, Tornavento in 1636, Leucates in 1637, La Rota in 1639, Casale and Turin in 1640, Wolfenbuttel in 1641, Kempen and Llerida in 1642, Rocroi in 1643, Friburg in 1644, Allerheim (or Noerdlingen) and Lhorens in 1645, Zusmarchausen in 1647, and Lens in 1648.