Theodosius I signs Edict of Thessalonica in 380 CE, making Christianity the official state religion of the Roman Empire.
In 395, after winning two destructive civil wars, Theodosius I died. He left a collapsing field army, and the Empire divided between the warring ministers of his two incapable sons. Goths and other non-Romans became a force that could challenge either part of the Empire. Further barbarian groups crossed the Rhine and other frontiers. The armed forces of the Western Empire became few and ineffective, and despite brief recoveries under able leaders, central rule was never again effectively consolidated.
Wikipedia - Fall of the Roman Empire
So my question is this - there’s only 15 years between the acceptance of Christianity as the state religion and the collapse of the state. What were the effects of forced conversion in the late western Roman empire, and did it accelerate or delay the fall of the empire?
I haven’t read much about the theological dimensions of the later stages of the Roman Empire. But I would contest the premise of the question. Instead I would argue that the Western Roman Empire more or less continued until the death of Theoderic the Great in 526. Yes, in name he wasn’t Roman Emperor, but only because of the might of the Eastern Roman Empire, whose regents would have been irate if he called himself that. But he was considered to be a Roman Emperor by many Roman citizens of the time, not only largely accepting him, but in many cases even celebrating him for trying to restore old buildings, roads, institutions etc.