"The Tragedy of St. Helena" by Sir Walter Runciman is a historical account written in the early 20th century. The book provides an analytical view of Napoleon Bonaparte's exile in St. Helena, emphasizing the complexities of his character and the treatment he received during his captivity. It aims to reassess the common perceptions surrounding Napoleon, highlighting his humanity and the injustices he faced. The opening of the text sets the stage by presenting the author's reflections on how opinions about Napoleon were shaped among British sailors and their experiences of his character, juxtaposed with the narrative constructed by the British government. The preface discusses the author's transformation from an anti-Napoleonic stance, influenced by sailors’ tales and literature, to a more sympathetic view of the exiled emperor after extensive research. Runciman’s argument centers on the cruelty of his treatment, notably under Sir Hudson Lowe's governance, and suggests that public perception may eventually recognize Napoleon's plight as a significant moral failure of the British authorities. (This is an automatically generated summary.)