John Stuart Mill, born on May 20, 1806, in London, England, stands as a monumental figure in the annals of political philosophy and economics. Known for his profound influence during the 19th century, Mill's intellectual contributions span a variety of fields, including political science, ethics, and economics. A quintessential utilitarian, Mill's works built upon and refined the doctrines of his predecessors, most notably Jeremy Bentham. His seminal essay 'On Liberty' (1859), advocates for individual freedom and protection against the tyranny of the majority, firmly entrenching him as a vanguard of liberal thought. Subsequent works like 'The Subjection of Women' (1869) and 'Utilitarianism' (1863) further illustrate his commitment to individual rights and social reform. Mill's autobiography, which provides a window into the intellectual rigour of his formative years, also contributes to an understanding of his psychological and philosophical development. His voluminous contributions have been compiled in 'The Collected Works of John Stuart Mill', serving as a testament to his enduring legacy. Mill's rigour, analytic clarity, and advocacy for the harm principle remain touchstones in discussions of ethical and philosophical issues.