Historians compile list of "the most stressful years in world history" - do you agree?

[Frodo]

451 AD should at least be considered a runner-up.  As much as the British during the First World War cast the Germans under the Kaiser as the 'Huns' for propaganda purposes, the real Huns under Attila were on the verge of conquering all of western Europe until the combined might of the (Western) Romans, Alans, and Visigoths at the battle of the Catalaunian Plains stopped them in their tracks.  Like the battle of Antietam, it was a stalemate but it robbed the Huns of their momentum, stripped them of their myth of invincibility, and Attila died a few short years later.  The heavy losses suffered by the Visigoths and Alans as well as the Romans ensured Frankish dominance over Gaul, and established more broadly that Europe's destiny would be determined by the Germanic tribes that later spawned kingdoms that eventually became the countries we know them today.