Iban migration from Indonesian Borneo through Kumpang.
While Iban leaders such as Jelian, Gelungan and Langkup were leading their followers on migrations into Sarawak through the Undup tributary, other leaders led migrations into the Batang Ai through the Kumpang, a tributary which joins the Batang Ai above Engkelili.
The first chief who led his followers to descend the Kumpang was Lanong. As he was the first migration leader to enter the new country, and he and his people settled permanently on the banks of Kumpang. They called themselves the Kumpang Dayaks.
Another chief who led his followers to migrate to Sarawak from Indonesian Borneo and used this route was Medan. He and his people first settled temporarily in the Kumpang but later moved down to Sengkarong below Engkilili. Medan was a famous ancestor of the Belambang people who to the present-day live in the area lying between the Kumpang and Undup tributaries of the Batang Lupar. They were followed by Ambau (not Pateh Ambau) who came later with Kanyong and settled at Tanjong Melarang, and Semalanjat who settled at Bungkap. The latter is a well known ancestor of the Bengap Dayaks.
From the Tiang Laju range Gunggu led his people to settle at Meriu near Engkilili. At this place they separated; some settled with the Belambang below Engkilili and others went to the Lemanak River, a right tributary of the Batang Lupar whose mouth is not far below Engkelili.