The Vicariate Apostolic of Sahara (Latin: Vicariatus Apostolicus Saharensis) is a former Roman Catholic missionary jurisdiction in colonial Algeria and Libya.
Eight years after the journey of the French explorer Henri Duveyrier (1859–61), which had important scientific results, Pope Pius IX on 6 August 1868 appointed the Archbishop of Algiers, Charles Lavigerie, as delegate Apostolic of the Sahara and the Sudan.
The first attempt was made in December, 1878, by Menoret, Paulmier and Bouchand; they were slain in April, 1876 by their Touarag guides, being the first martyrs of the Society of White Fathers, and the cause of their beatification was introduced at Rome in 1909.
As early as February, 1891, the station at Ouargla, also in northern Algeria, suppressed in 1876, was re-established, and in October Harquard sent thither six armed "pioneers" who wrote to the cardinal: "We shall endeavor to hold high the banner of the Sacred Heart and the flag of France."
The White Sisters founded hospitals at Ghardaïa and El Tbiod Sidi Cheikh, thus gaining the confidence of populations which were hostile to France.