Chalcedonian Christianity refers to the branch of Christianity that adheres to the definitions established by the Council of Chalcedon in 451 AD. This council affirmed the belief in the dual nature of Christ, stating that He is both fully divine and fully human, united in one person. This doctrine is essential for many mainstream Christian denominations, including Roman Catholicism and Eastern Orthodoxy. The Chalcedonian Definition aimed to address and clarify theological disputes regarding the nature of Christ, particularly against various heresies. It emphasized that while Christ's two natures remain distinct, they coexist without confusion or separation, shaping the foundation of Christological beliefs in Chalcedonian traditions.