Final answer:
Roman soldiers were overwhelmed by intense military expectations, brutal discipline, and declining leadership. Battles against barbarian tribes, especially the Goths, breached Rome's defenses, symbolizing the collapse of Roman military might and unity. The defeat in the Teutoburg Forest highlights these vulnerabilities.
Step-by-step explanation:
Roman soldiers during attacks were overwhelmed by a variety of challenges through different periods. Service in the army was intense and grueling, with expectations of marching over 20 miles a day with heavy equipment and under brutal discipline. Fear of punishment, such as summary execution for infractions like falling asleep on guard duty, was a constant.
As the Roman Empire faced external threats, the quality of leadership declined and the military might that once successfully defended Roman sovereignty began to falter. Under-resourced and under-manned, armies in the West fell into a decline. The Goths and other barbarian tribes, pressured by the Huns, overran borders and territories, culminating in dramatic events like the sacking of Rome that punctured the myth of Roman invincibility.
The most famous military defeat was in the Teutoburg Forest in 9 CE, where several legions were wiped out, halting Roman expansionist plans across the Rhine. This event, among others, illustrates the collapse of Roman military discipline and cohesion under pressure.