This article investigates the relationship between language policy and spatial production. The regulation of language is inextricably tied to extra-linguistic—social, cultural, political and economic –processes permeating the broader sociolinguistic ecology. The article argues that language policy creates territorial space in this otherwise open ecology. Territories emerge from the tension between two dimensions of language policy: the free-flowing language activities in circulation and the coordinated regulation of boundaries in space. The article examines the relation between these two dimensions through the concepts of ‘languaging’ and ‘assemblage’. This theoretical argument is illustrated with the developing Guangdong-Hong Kong-Macao Greater Bay Area in southern China as an example. The example suggests two theoretical implications. First, language policy regulates not only linguistic features or varieties but the coordination between linguistic and extra-linguistic practices of languaging. Second, territorial spaces are created not by externally imposed orders but by assemblages formed within the processes of languaging.