Napoleon was a horse fanatic - though not a terribly classy-looking rider by all accounts - who preferred arabs and expounded selective breeding and the formation of the French national stud.
This book chronicles what Hamilton has gleaned of the horse's career - a difficult task some two hundred years after events. As a result this book is heavy on Napoleon's background, although this is presented in a fairly readable manner.
Hamilton finds that there is some confusion about Marengo's origin - was he originally from Egypt and named Ali? Did his name change after the battle of Marengo?
After his career with Napoleon was over, the horse found his way to England, where he was exhibited widely. He died there at the age of 38.