Who were the first human ancestors to create fire?

We don't know how exactly, because the 'controlled' use of fire first happened some 400,000 years ago. Chances are that in the beginning burning or glowing pieces of wood were taken where a bush fire had burned, and that fires and embers were kept alive by a designated member of the tribe. The knowledge of creating heat and starting fires by friction or sparks from flint is also very old, and was probably stumbled on by accident. So there is not much difference between the way earliest humans started fires and the way boy scouts do it today.