Candidates preparing for the UPSC examination should be knowledgeable about significant historical figures such as Mahatma Gandhi, Dr. B.R. Ambedkar, and Sardar Vallabhbhai Patel. Understanding their contributions and ideologies provides context for India's struggle for independence and subsequent nation-building. Additionally, familiarity with global historical figures can also enhance understanding of international relations and context. Gaining insights into these personalities is crucial to developing a well-rounded perspective, as they deeply influence India's current socio-political framework.