The significance of national integration as a theme in UPSC topics lies in fostering a unified and harmonious society. It emphasizes the importance of understanding cultural diversity, regional disparities, and historical contexts that influence contemporary issues in India. Knowledge of national integration helps aspirants grasp existing societal challenges related to communal harmony, social justice, and equitable development. This understanding is essential not only for theoretical knowledge but also for framing policy solutions as future civil servants, thereby promoting national unity.