Early Church History refers to the period following the life of Jesus Christ and the establishment of the Christian Church in the first few centuries AD. After Jesus' resurrection, his followers, known as apostles, spread his teachings throughout the Roman Empire. Key figures like Peter and Paul played significant roles in this expansion, establishing communities of believers and writing letters that would later become part of the New Testament. During this time, the Church faced various challenges, including persecution from the Roman authorities and internal disputes over beliefs and practices. The Council of Nicaea in 325 AD was a pivotal moment, as it sought to unify Christian doctrine and address controversies, ultimately shaping the future of Christianity as it spread across Europe and beyond.