On 1 August 1558, three weeks after the alarming defeat of the French army at Gravelines, Henri II arrived at Laon, where he was joined by a duke of Guise who was busy sending out spies to reconnoitre the enemy's positions and asking for details of enemy movements company by company. While the King took up residence at the cardinal of Lorraine's Château of Marchais, the duke moved on 3rd to Pierrepont, near Marle, sending out letters of instruction for the assembly there of a great army. On 8 August, the King himself arrived to dine and at 1 o’clock to review in a broad plain the most splendid army assembled in one place by a King of France in the Renaissance period. Monluc remembered that ‘it was the finest and largest army a King of France had ever had’ and that it took three hours to pass in review before the King. The Venetian ambassador, thought it extended for 6 or 7 Italian miles. Rabutin, who was also there, noted that ‘never could be remembered an army in which there were so many foreigners, even German cavalry amounting to 8000 horse.’ The army, he said, was drawn up in a great crescent with the avant-garde and rear guard at each extremity and the ‘battle’ in the centre. ‘Thus was ranged this fine and powerful army that the King, accompanied by many great princes of his realm, inspected from one end to the other. It is certain that His Majesty took a particular pleasure in seeing so many princes, great lords, captains, gentlemen and generally so many men assembled there, ready to sacrifice their lives for his service and to support his cause. But what gave greatest cause for amazement, and by which could be known all the horrendous powers and inventions of the bloody god of war Mars, was to hear the roar of the artillery and the discharge of so many arquebuses and pistols by the Reiters. It seemed as though heaven and earth were exploding in thunder and that the Almighty wanted to smash the world to pieces.’ Rabutin tells us that the royal inspection lasted for six or seven hours amidst the heat and dust of the August afternoon.

According to Rabutin, the 1750 lances of the gendarmerie were joined by 1400 light horse and 8000 German pistoliers (including Wilhelm of Saxony's 7 cornets). .