This book offers a comprehensive and critical exploration of English literature from its ancient foundations to its modern and contemporary expressions. It brings together literary history, theory, criticism, and cultural analysis to present a balanced understanding of how English literature has evolved across centuries, regions, and intellectual movements. The discussion moves fluidly between classical philosophical influences, major literary periods, and the development of critical thought, highlighting how texts respond to social, political, and linguistic change. The book examines the growth of literary forms such as poetry, drama, fiction, and prose, while also addressing translation, language variation, and cross-cultural literary interactions. Special attention is given to canonical writers as well as lesser-discussed traditions, including American, British, and Indian English literature. Critical Encyclopaedia of English Literature: Ancient and Modern is designed to serve as a reliable reference and analytical guide for students, researchers, teachers, and readers seeking a deep and structured insight into the vast field of English literary studies.