This is the first Encyclopaedic dictionary in English which defines both for laymen as well as scholars the names and concepts associated with this historic day, and the events that happened before and after it. This book is a must read for anyone who wants to understand this epoch-making event which, to this day, continues to influence not only the Shia community but also other faith groups who venerate Husayn as the martyr who laid down his life to speak truth to power and as the heroic figure who redefined the paradigm of the struggle against tyranny and oppression.