Knights armor is actually much more flexible than you thought. Medieval knights wore
metal armor of iron or steel to protect themselves from archers and the long swords of
opponents. From the 9th century CE, chain mail suits gave protection and freedom of
movement until solid plate armour became more common in the 14th century CE.
The short video is mesmerizing. The armor and its moving mechanisms are
impressive, straight out of Dark Souls. That popular image of knights as slow-moving warriors locked in inflexible armor? You Died.