And one might add that Medieval times and the period “Dark Ages” is most often applied to are distinct. The time between the collapse of the Western Roman Empire around 450 AD and the rise of Charlemagne as Holy Roman Emperor was indeed dark. Classical knowledge was forgotten, Christianity itself was largely displaced by paganism everywhere but Ireland and a small territory around Rome itself, and few written records were made of what went on, leaving later scholars in the “dark”. Christian missionary and by conquest reconversion of the west and the prolific writing and scholarship of the monasteries switched the lights back on.
From 500 to 700 (give or take a few decades) was generally not a pleasant time, because people had to scramble to make the best of things mostly on their own. It was rough.
As the Carolingian Empire developed, as Italy formed stable principalities, as England became unified and well-managed, things got much better.
No age is perfect, but from 800 to 1300 (give or take a few decades), things were not too bad. The Mongols and the Black Death (1348)were dark events, but Europe went on to enter the period we call the Renaissance. A rather troubled time in its own way, but one we think highly of.
The true Middle Ages (roughly 800 to 1300) had a lot to recommend it. Europe forged a special identity then, and we still benefit from that.
Classical knowledge was forgotten, Christianity itself was largely displaced by paganism everywhere but Ireland and a small territory around Rome itself
Most of the territory of the Empire was invaded and settled by "Christian" Germanic tribes. They were mostly Arians, but still Christians.
The two main exception of which I'm aware were the early Franks and Anglo-Saxons. Also I think the Lombards were still partly pagan when they invaded Italy.
“Classical knowledge was forgotten, Christianity itself was largely displaced by paganism ...”
From 632-1499, classical knowledge was destroyed by the invading Islamic armies of Muhammad and his disciples who fought 528 battles against western armies, and enslaved western women; Christianity was displaced by Islam. Fear of Islam stemming from this horrific period still pervades western civilization today.