Upon his ascension to Yani, Ya Naa Alasani enskinned his uncle Korli Naa Bukari Narkaw to the now vacant skin of Karaga. Ya Naa Alassani also appointed his brother Kalim to Mion, deskining Mion Lana Salifu, and his uncle Bukari to Savelugu. When Yo Naa Bukari died in the early 1900, Ya Naa Alassani appointed his brother Mahama to Savelugu. These appointments are important because at that point there was no one from Andani yili on a gate skin. Therefore Andani yili could not get to Yani as the rotation system demanded. It must be noted that the appointment of chiefs to the divisional chiefdoms is left at the sole discretion of the Ya Naa and his elders. Whoever he wills is appointed.
After the ascension of Ya Naa Alasani to the skins of Yani Dagbon was partitioned into Togoland Dagbon and British Dagbon. On November 14, 1899, the colonial powers of Britain and Germany signed a convention to establish boundaries to their colonial territories. The British Dagbon mainly consisted of Western Dagbon, stretching from around Mion (Sambu) to Tamale. Whereas Yendi, Mion (Sambu) and most of Eastern Dagbon made up Togoland Dagbon, under German administration. The partition of Dagbon created intense friction between Ya Naa Alasani on the one hand and Yani gate skins in Western Dagbon on the other. Especially, his uncle Karaga Naa Bukari Narkaw.
After the partition of Dagbon the British administration instructed all Western Dagbon chiefs to sever all links and communication with Yani. In fact when Yo Naa Mahama (chief of Savelugu and brother of Ya Naa Alasani) was found to be communicating with Ya Naa Alasani he was removed as chief of Savelugu and thrown into British jail. Karaga Naa Bukari Narkaw heeded the instruction of the British and severed all communication with Yendi. Karaga Naa Bukari was so cooperative with the British administration that he was described as one of the most loyal chiefs in Dagbon.
The partition of Dagbon saw various chiefs in Western Dagbon take advantage of the situation to advance and grow their chiefdoms. Upon the death of Mion Lana Kalim in 1911, Karaga Naa Bukari Narkaw assumed the capacity of “British Dagbon Ya Naa” and enskinned son of Ya Naa Andani II as British Mion Lana. At the same time Ya Naa Alasani appointed his son Naa Abdulai as German Mion Lana. Thus there were two chiefs for Mion. The British Mion Lana made Kpabia the seat of Mion whiles the German Mion Lana remained in Sambu which had fallen under Germany jurisdiction.
It is narrated that just before the partition of Dagbon Gulkpe Naa (chief of Tamale) was traveling in Yendi. He could therefore not return to Tamale for the duration of the partition. Dakpema of Tamale thus made claim as the chief of Tamale. Under this claim Dakpema was able to convince the British to move the capital of the Northern Territories to Tamale from Gambaga.
After the removal of Yo Naa Mahama, the second son of Ya Naa Andani II, Naa Bukari, was enskinned chief of Savelugu. Other son’s of Ya Naa Andani II had also taken the skins of Sagnarigu, Tampion, Zangbalun, and Kpatinga. Thus, the Andani gate grew very powerful in Western Dagbon under the British.
Ya Naa Alasani died on January 17, 1917 during the First World War and the partition of Dagbon. In 1917, however, Togoland Dagbon was under British control. Three years earlier, in 1914, the British invaded and took Yendi without much resistance from the Germans. There was, however, uncertainty regarding the outcome of the war. The British did not, therefore, allow the enskinment of a successor to Ya Naa Alasani. The Gbon Lana of Ya Naa Alasani, Mion Lana Abdulai, served in the role of Ya Naa.