[2] The extent of Jaako territory is estimated to have been around 300 square miles (780 km2), including Croker Island, which they called either Mangulalgut or Margo.
They also held land on the area on the Cobourg Peninsula on the mainland opposite, and were also present at Raffles Bay.
[3] The early explorer G. Windsor Earl stated that the Jaako appeared to be formed from the "amalgamation" of two distinct tribes.
Earl states that: The people of this tribe are generally small in stature, ill-formed and their countenances are forbidding and disagreeable.
[5]Their leader at the time was, again according to Earl, a certain Mimaloo, whom together with another warrior, Loka, later killed by the Makassans in revenge for the death of one of their own, was regarded as highly aggressive.