Since Mitchell's main objective was to show the French threat to the British colonies, there is a very strong pro-British bias in the map, especially with regard to the Iroquois. The map makes clear that the Iroquois were not just allies of Britain, but subjects, and that all Iroquois land was therefore British territory. Huge parts of the continent are noted as being British due to Iroquois conquest of one tribe or another. French activity within the Iroquois claimed lands is noted, explicitly or implicitly, as illegal.