Franco - Moroccan War The Franco - Moroccan War ( 1844 ) was a series of conflicts fought between France and the Saadi sultanate of Morocco . The principal cause of war was the retreat of Algerian resistance leader ` Abd al - Qādir into Morocco following French victories over many of his tribal supporters during the French conquest of Algeria . Prelude . Abd Al - Qādir had begun using northeastern Morocco as a refuge and a recruiting base as early as 1840 , and French military movements against him heightened border tensions at that time . France made repeated diplomatic demands to Sultan Abd al - Rahman to stop Moroccan support for Abd al - Qādir , but political divisions within the sultanate made this virtually impossible . Tensions were heightened in 1843 , when French forces chased a column of Abd al - Qādir supporters deep into Morocco . These men included Alawī tribesmen from Morocco , and French authorities interpreted their actions as a " de facto " declaration of war . While they did not act immediately , French military authorities threatened to march into the sultanate if support for Abd al - Qādir was not withdrawn , and the border between Algeria and Morocco properly demarcated so that defenses against future incursions could be set up . By early 1844 French troops had constructed a fortification at Lalla - Maghnia , the site of a Muslim shrine near Oujda , and clearly not within territory traditionally claimed by the Ottoman Regency of Algiers . An attempt to dislodge these troops peacefully in late May 1844 failed when Alawī tribal fighters fired on the French and were eventually driven back to Oujda . Rumors surrounding this incident ( including reports that the shrine had been defiled and that French troops had entered Oujda and hanged to governor ) fanned the flames of jihad in Morocco . Amid escalating troop buildups and skirmishes in the frontier area , French Marshal Thomas Robert Bugeaud insisted that the border be demarcated along the Muluwiya River , a position further west than the Tafna River which Morocco considered to be the border . Military campaign . The war began on August 6 , 1844 , when a French fleet under the command of the Prince de Joinville conducted a naval bombardment of the city of Tangiers . The conflict peaked on August 14 , 1844 at the Battle of Isly , which took place near Oujda . A large Moroccan force led by the sultan ' s son Sīdī Mohammed was defeated by a smaller French imperial force under Marshal Bugeaud . Essaouira , Morocco ' s main Atlantic trade port , was attacked in the Bombardment of Mogador and briefly occupied by Joinville on August 16 , 1844 . Treaty of Tangiers . The war was formally ended on September 10 , with the signing of the Treaty of Tangiers , in which Morocco agreed to arrest and outlaw Abd al - Qādir , reduce the size of its garrison at Oujda , and establish a commission to demarcate the border . ( The border , which is essentially the modern border between Morocco and Algeria , was agreed in the Treaty of Lalla Maghnia . ) Sultan Abd al - Rahman ' s agreement to these terms , which amounted to a capitulation to French demands , threw Morocco into chaos , with Alawī and other tribal areas threatening secession in support of Abd al - Qādir , and calls in some circles for al - Rahman to be deposed in favor of Abd al - Qādir . The sultan and his sons eventually regained control over the sultanate , and were able to marginalize Abd al - Qādir ' s calls for jihad by pointing out that without their support , Abd al - Qādir was not a " mujahid " , or holy warrior , but merely a " mufsid " , or rebel . By 1847 the sultan ' s forces were in jihad against Abd al - Qādir , who surrendered to French forces in December 1847 .