Scientists at Leeds and Bradford universities used pet bog data to show that changes in climate believed to coincide with population falls in fact occurred at least two generations later.
Ian Armit, of Bradford University, said social/economic stress were a more likely cause.
The findings have significance for modern climate change debates which, says Professor Armit, are too quick to link climate events with changes in population.
“Often, in examining the past, we are inclined to link evidence of climate change with evidence of population change. Actually, if you have high quality data and apply modern analytical techniques, you get a much clearer picture and start to see the real complexity of human/environment relationships in the past.”