The threat of conquest from León, together with a rapid-fire series of Cordoban successes against other Muwallad rebels in the 910s-920s under Abd ar-Rahman III, is likely to have contributed to the eventual surrender of the Marwan clan to the Cordoban Caliphate in 930. Under the Caliphate (929-1031 CE), Marvão again fell under the auspices of the territorial district, or kūrah (Spanish: Cora) of Mérida, which comprised much of modern-day Portugal north of the Algarve, and comprised the Lower March (or buffer zone) bordering the Christian north.