By this time Napoleon Bonaparte made the poor decision to take Spain by force and replace King Charles IV. The French introduced 70,000 French troops into Spain and on 16 February 1808 seized control of a number of fortresses and cities. On 2 May 1808, the Spanish people rebelled against the French occupation forces, starting the Peninsular War. Laval and Claude Rosthollant were the brigade commanders in Bernard-Georges-François Frère's 3rd Division which belonged to Pierre Dupont de l'Étang's 2nd Corps of Observation of the Gironde. Frère's division included the 1,160-strong 15th Light Infantry Regiment, the 2,870-man 2nd Legion of Reserve, and the 1,174-strong 1st Battalion of the 2nd Swiss Infantry Regiment. The division was detached from the corps and did not share in the Bailén disaster. Instead Frère was sent from Madrid to reopen communications with Marshal Bon-Adrien Jeannot de Moncey's corps in its retreat after the Battle of Valencia. The two forces united on 8 July 1808 and withdrew to Madrid. Laval was promoted to general of division on 1 April 1809.