chiefs of all tribes in Montenegro. The territorial expansion of Montenegro continued, and after the Balkan Wars (1912–13), it included substantial parts of Herzegovina, Serbia and Albania. Since 1880 the ambitions of Nikola I collided with those of Obrenović and Karađorđević dynasty for leadership of the Serbs. Montenegrin nationalism (federalism) eventually suffered from the political activity of young Montenegrins living in Serbia. During the Podgorica Assembly (1918) which decided the fate of Montenegro as either an independent state (supported by the Greens) or a united part of the Kingdom of Serbia (supported by the Whites), the tribes were divided, even internally. The Greens consisted of the highland tribes of Moračani, Piperi and Rovči, the Katun clans of Bjelice, Cetinje, Cveto and Cuce and the Hercegovinian tribes of Nikšići and Rudinjani. The Greens ethnically declared themselves as Serbs, but did not support, what they saw, as a Serbian annexation of the Montenegrin state. However, the Whites supported by the rest of the tribes eventually won. During World War II, the tribes were internally mainly divided between the two sides of Chetniks (Serbian royalists) and Yugoslav Partisans (communists), that were fighting each other for the rule of Yugoslavia. As a result, the conflict spread within the tribal and clan structures. Anthropology Czech historian Konstantin Josef Jireček (1918) considered that the population of Duklja was a very mixed population of newly arrived Slavs and older people like Albanians and Romanians. Croatian historian Milan Šufflay (1925–1927) considered that the Vlach-Albanian-Montenegrin symbiosis is seen in the etymology of the names, in Piperi, Moguši, Kuči, and the surnames with suffix "-ul" (Gradul, Radul, Serbul, Vladul), and toponymical names of mountains, Durmitor and Visitor. Serbian historian Vladislav Škarić (1918) considered that many brotherhood names, like Sarapi, Radomani and others in Montenegro, belonged to migrants from central Albania, while Bukumiri from Bratonožići, Vajmeši from Vasojevići, Ibalji from Herzegovina came from northern Albania. Serbian ethnologist Jovan Cvijić (1922) noted the Slavic assimilation and migration of many Albanian groups of Mataruge, Macure, Mugoši, Kriči, Španji, Ćići and other Albanians/Vlachs who were mentioned as brotherhoods or tribes. He considered that all gornji ("upper") tribes lived in the parts of currently Serb tribes in Brda and Old Herzegovina, and that many groups were assimilated into the tribes of Piperi, Kuči, Bratonožići, Bjelopavlići among others, who preserved their old name. American cultural anthropologist Christopher Boehm stated that some clans descended from the pre-Slavic