Relevant aspects of Indian history for UPSC candidates include the evolution of the freedom struggle, essential social reform movements, and the establishment of the Constitution. Key events like the integration of princely states, the impact of colonial policies, and significant figures such as Mahatma Gandhi and Dr. B.R. Ambedkar are vital for understanding contemporary governance. Additionally, awareness of India's cultural history, regional diversities, and historical conflicts helps candidates appreciate the country's complexities and better prepares them for the civil services role.