“The book presents an accurate description of the ideas and methods developed to face the first variational problems, essentially from the Brachistochrone in the seventeenth century to the very first years of the nineteenth century, covering overall a little more than a century. … The book is the result of the fruitful cooperation between a specialist in the history of sciences and a well-known researcher in the Calculus of Variations … .” (Arrigo Cellina, Mathematical Reviews, May, 2017)“The authors succeeded in adding a very valuable book to the literature available on the history of the calculus of variations. The book is full of the mathematics of the masters and the authors have taken pain to clarify even the details in nowadays mathematical notations.” (Thomas Sonar, zbMATH 1350.01001, 2017)