Learn some history BBC

The BBC have an article on their news pages reporting that "Some 80,000 Islamists have met in the Indonesian capital, Jakarta, to press for the re-establishment of a caliphate across the Muslim world." Unfortunately at least one fact is a little suspect namely "A caliphate - or single state for Muslims - last existed in 1924." Really, which countries were formed into this caliphate? I thought it was just that the ownership of the caliphate was held then by the Ottoman Empire