What 'felled" the mammoths, Rhinos, fox, tigers etc. was rapid freezing and burial under hundreds of feet of ice and snow. As some samples show (complete bodies with still edible meat in some cases) they were crushed by this ice while they were grazing on tropical vegetation. They were killed by a catastrophic event. Since no human bodies have ever been found in the regions these animals are found, it's not very likely that there were any human settlements in the area at the time.
It's likely that human settlement came much later as the ice receded.