History Decoded: The 10 Greatest Conspiracies of All Time

History Decoded: The 10 Greatest Conspiracies of All Time is a 2013 non-fiction book by Brad Meltzer. It contains a series of investigations into history’s greatest conspiracies. Included in the book at the introduction to each chapter is an envelope that holds facsimiles of relevant evidence: John Wilkes Booth's alleged unsigned will, a map of the Vatican, John F. Kennedy's death certificate. It is a companion to the show Brad Meltzer's Decoded on History Channel. According to WorldCat, the book is in 896 libraries.

Contents
The book contains investigation into the following mysteries:
 * "John Wilkes Booth : Was Lincoln's Assassin Apprehended?"
 * "Confederate Gold : Stolen Treasure or Hidden Wealth of a New Confederacy?"
 * "The Georgia Guidestones : America's Stonehenge"
 * "DB Cooper : American Outlaw"
 * "The White House : Where is the Cornerstone of Democracy?"
 * "The Spear of Destiny : History's Most Sacred Relic"
 * "The Real Da Vinci Code : Did Leonardo Predict an Apocalypse?"
 * "Is there any Gold in Fort Knox?"
 * "UFOs : Inside Roswell and Area 51"
 * "The Kennedy Assassination : the Truth is out There."