Late Antiquity refers to the period between the 3rd and 8th centuries AD, characterized by significant religious, cultural, and administrative changes. During this time, the Roman Empire underwent a transformation that led to the emergence of a new social, political, and religious order.

Religious Changes:

1. Emergence of Christianity: Christianity became the dominant religion during this period, replacing paganism, which was the primary religion of the Roman Empire.

2. Rise of Monasticism: Monasticism emerged as a significant religious movement during this period, with monks and nuns living in isolation from the world to devote their lives to prayer and meditation.

3. Development of Church Hierarchy: The Church hierarchy developed during this period, with the establishment of a patriarchal system of bishops, archbishops, and popes.

Administrative Changes:

1. Division of the Roman Empire: The Roman Empire was divided into two, with the Western Roman Empire collapsing, and the Eastern Roman Empire (Byzantine Empire) continuing to thrive.

2. Emergence of Feudalism: Feudalism emerged as a new social and economic system, with feudal lords controlling the lands and the peasants working on them.

3. Development of the Byzantine Empire: The Byzantine Empire emerged as a significant power during this period, with Constantinople becoming the new capital of the Roman Empire.

Conclusion:

Late Antiquity was a period of significant changes, marked by the emergence of a new social, political, and religious order. The rise of Christianity, monasticism, and the Church hierarchy, the division of the Roman Empire, the emergence of feudalism, and the development of the Byzantine Empire were some of the significant changes that took place during this period.