The Punans most likely started migrating to Kakus watershed as early as in the 16th century (1700) – albeit in small groups, from Ba River. These groups initially settled on the upper reaches of Kakus cultivating the lands and exploiting nearby jungle resources, particularly bird nest from the caves as source of income.
The migrations heightened in the middle of 18th century (circa 1770-1790) period (Guerreiro 1988), as the exodus of Kayan from Apo Kayan in Kalimantan began moving down Rejang River forcing Punan fleeing the region to avoid subjugation. Kakus River was largely inhabited at the time, with the Tatau occupying only the Tatau and Anap watershed. The Iban has yet to move in.
The fertile undulating plain of Kakus and Tatau River were all to the Punan and Tatau peoples, albeit with some friction when the latter began moving downriver to Anap and Tatau Rivers. Soon however, animosity turns to friendship when one of the Punan – Tugang married into a Malong family, the heir of the longhouse and formed his own Punan quarters among the Tatau (c.f S.G Jan 22nd 1878). Malong refers to one of Tatau longhouse in the area (Sandin 1970), believed to be near the present day Tatau town.
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