that's not what you think it means...
A caliphate (Arabic: خِلَافَة khilāfah) is an Islamic state under the leadership of an Islamic steward with the le of caliph (/ˈkælɪf, ˈkeɪ-/; Arabic: خَلِيفَة khalīfah), a person considered a politico-religious successor to the Islamic prophet Muhammad and a leader of the entire ummah (Muslim community).
In other words, the caliph is the proclaimed leader of all the muslim world, including people and land. Do you understand how that works? It doesn't actually mean they 'own' land.
Please do keep reading, you're still far away from understanding how the Muslim world works.