His physical handsomeness and the qualities of his mind had made Abdelkader popular even before his military exploits. Of medium height, lithe and elegant, with regular features and a black beard, his demeanour was exceptionally refined, and his life-style simple. He was known as a religious and educated man who could excite his co-religionists with his poetry and oratorical eloquence.
Algeria was an Ottoman regency when the French army landed there in 1830. The government was controlled by a dey (governor) and by the Turkish Janissaries who had chosen him. These rulers, supported by the Koulouglis (people of mixed Turkish and Algerian ancestry) and by certain privileged tribes, and aided by the fact that they were of the same religion as the people, long held Algeria firmly in their grip.
Nevertheless, the Algerians detested them, and there were continual rebellions in the early 19th century. As a result, the country was left too divided to oppose the French invaders.
The western tribes laid siege to French-occupied Oran and tried to organize themselves, unified by their common Muslim religious sentiment, which was cultivated by the schoolmasters and particularly by members of the religious brotherhoods. The leader of one of the brotherhoods, Mahieddin, director of the zāwiyah (religious school) near Mascara, was asked to lead the harassment of the French troops in Oran and Mostaganem.
In November 1832 the aging Mahieddin had his young son Abdelkader elected in his place. The youth, already renowned for his piety and military prowess, took over the war of harassment. The ensuing Desmichels Treaty of 1834 gave him the whole interior of the Oran, with the title commander of the believers. In a move to unify his new territories, Amīr Abdelkader, taking advantage of this treaty, imposed his rule on all the tribes of the Chelif, occupied Miliana and then Médéa, and succeeded in defeating General Camille Trézel at Macta. Although pressed by generals Bertrand Clauzel and T.R. Bugeaud, he managed to rally support from Algerians who had become indignant over the French use of violence. By able negotiation, he convinced General Bugeaud to sign the Treaty of Tafna (1837), which further increased his territory and made him master of the whole interior of Oran and the Titteri, with the French having to be content with a few ports.