Between 200 CE and 500 CE, several significant changes occurred in Europe and East Asia.
In Europe, the decline of the Roman Empire continued and eventually led to its collapse in 476 CE. This period saw the emergence of new Germanic kingdoms, such as the Visigoths and the Ostrogoths, as well as the rise of the Byzantine Empire in the eastern Mediterranean. Additionally, the spread of Christianity continued, and by the end of this period, it had become the dominant religion in the Roman Empire.
In East Asia, China during the Han Dynasty reached its peak of power and culture, but by the end of the 2nd century CE, the empire began to decline and was eventually replaced by a number of smaller kingdoms. Additionally, Buddhism began to spread from India to China during this period, and by the end of the 5th century CE, it had become a significant religious and cultural influence in China.
In Korea and Japan, the Three Kingdoms period was coming to an end, and a single ruling state started to emerge. This period also saw the spread of Buddhism, Confucianism and Taoism in the region.
In India, the Gupta Empire rose to power and established a golden age of Indian culture and science, with advancements in mathematics, astronomy, and the arts. Buddhism continued to be an important religion during this time.
Overall, Europe and East Asia experienced a period of political and cultural change and transition during this time period, as well as the spread of new religions and the emergence of new political powers.