Book excerpt: This book presents the basic fundamentals of descriptive archaeoastronomy and its application to the astronomical descriptions found in ancient Indian scriptures. Archaeoastronomy is a branch of positional astronomy that helps to determine the epochs of ancient astronomical alignments and special astronomical events. In this book, only the descriptions of special stellar alignments and events found in ancient texts can identify the antiquity of the descriptions. India possesses a large volume of ancient scriptures like Vedas and Puranas which contain many astronomical descriptions as in ancient India positional astronomy was well developed. The antiquities of these texts are determined through archaeoastronomical techniques. Major events like Mahabharata War are dated and using these dates a chronology of ancient India is determined. The astronomically determined chronology is compared with the results from various archaeological, palaeoclimatological, geological and genealogical investigations of ancient India. This introductory book interests readers interested in unveiling the mystery involved with the protohistory of this ancient civilization.