What we “know” for certain in history often changes.  New studies, new information, new scholarship can challenge and change accepted facts, and undercut theories that have stood for decades or even longer.

Witness this article in today’s Guardian newspaper reporting that a new work by a well known archaeologist declares the Plague of 1348-49 spread so quickly through London that the carriers were not black rats, as previously thought, but human beings themselves.  Fascinating and a reminder that we ought not be too sanguine about what we know to be “the truth.”