Over the past 20 years or so, advances in archaeology have enabled us to test isotopes in human and animal teeth, showing possible places of origin and effects of diet; we can extract DNA and unlock the genome, not only finding living relatives but having a good guess at hair and eyes colour and other traits.
Now it seems even the planet itself can unlock some of the secrets of the past–in glaciers. According to an article in ANTIQUITY, a glacier has revealed the time of Thomas Becket‘s martyrdom, when, in penance, Henry II founded many religious houses as a penance. There was a massive rise in the use of lead to make the roofs of these buildings, and it was carried on the prevailing winds to the Alps where it ended up preserved in the ice of a glacier.
But this increased production was not all the ice showed. Apparently with every king’s death, there is a dip in lead mining which does not resume until the next reign. The scientists could see the timeline of all English kings mapped out in the ice.
Tests also showed that the 12th C had air pollution as bad as the Industrial Revolution due to the mining, which few would have expected.