I do feel a bit like an explorer setting out into parts unknown, peopled by unknown tribes.
He thought that the body could have been an infant of some unknown tribe of Indians.
In addition to the Greentown Indians, an early unknown tribe inhabited the area.
There were doubtless primitive and unknown tribes before the Picts.
New photographs of a hitherto unknown Brazilian tribe have caused great excitement around the world - and not just among anthropologists.
He was in the middle of a vast lake, surrounded by tribes unknown to him, and probably ferocious.
Along the way, he recruits a broken down, drunk prospector to help him track down the unknown tribe and rescue his sister.
Oh," he went on, "I had enormous dreams of discovering unknown tribes in Central Africa.
They fell under Andy's classification of an "unknown tribe."
Brennus is said to have belonged to an otherwise unknown tribe called the Prausi.