The actual phrase ‘Dark Ages’ itself derives from the Latin saeculum obscurum, which Caesar Baronius – a cardinal and Church historian – came up with around 1602. He applied the term exclusively to the tenth and eleventh centuries. However, and very significantly in his use of the term, Baronius was not decrying a state of scientific malaise, or a particularly turbulent political period – he’s talking about a lack of sources surviving from that time. Indeed, Baronius sees the cut off point for the dark ages to be the Gregorian reforms of 1046, following which we see a massive increase in surviving documentation.