Issue 21 of the biannual peer-reviewed journal Ostour has been published by the Arab Center for Research and Policy Studies and the Doha Institute for Graduate Studies. The issue features the following studies: "A Thematic Reading of Ancient Historical Geography: North Africa through Pliny's Natural History as a Case Study" by Zakaria Boukijij and Said El Bouzidi; "Transformations of the Urban Area in Volubilis during the Mauretanian Period" by Nabil Zairi; "The Iconographic Debate between the Umayyads and Byzantines between the Second Half of the 7th Century and the Beginning of the 8th Century CE: Ideological and Political Implications" by Al-Moez Omari; "The Cultural and Religious History of Modern Morocco" by Lotfi Bouchentouf; "Between Empires and Nation: Memories of the Great War and Iraqi National Identity" by Dina Khoury; "Subsistence Crises in Tangier during the Protectorate (1912-1956)" by Nabil Touihri; and "Memory and History in Modern and Contemporary Morocco" by Abdelaaziz Ettahiri. The issue's Translations section features one article: "A Critique of Local History: The Return of the Longue Durée from an Anglo-American Perspective" by David Armitage and Jo Guldi (translated by Mohammed Habida).

Book reviews include Hassan Hafidi Alaoui's analysis of The Historical Roots of the Maghreb: The Dialectic of Power, Society, and Sphere (during the First and Second Hijri Centuries/Seventh and Eighth Centuries CE), Lotfi Aissa's review of Between Two Temporalities: A Reading into the Past of Globalization, and Ahmed Elhabchi's review of Innovations and Religion in Morocco in the 19th and 20th Centuries. The issue concludes with the Primary Sources section, featuring Kheireddine Saidi's study "New Insights on Hamdan Khoja's Positions on the Algerian Question through Two Letters to the Sublime Porte (1834-1835)."