The process of formation of the State of Tuscany and the role played by important personalities, such as Cosimo I dei Medici is reviewed, through three centuries of Tuscan history, during the period when, before being united, Italy was composed of many little states. Starting from the crucial period of the war of Siena and Maremma, the author analyses some strategic and military elements, such as the control over the sea and the navigation flows in the Tyrrhenian Sea, as well as economic elements, such as the monopoly over iron extraction, as the Elba Isle (belonging to the Appiani family, Lords of Piombino), held the most extraordinary iron deposit of the Mediterranean Europe. The creation of a "modern" iron industry, obtained through the improvement of the iron factory of the Grand Duchy of Tuscany, is the result of Cosimo's choices. In the age of reforms, another figure emerges, with an important role: Bernardo Tanucci, a Tuscan man who became a Minister at the Court of Naples, who was involved in the fight against the baronial system and in the claims of the King of Naples over the Principality of Piombino, belonging to the Boncompagni Ludovisi, an important and most conservative aristocratic dynasty of the time. The author also analyses some other crucial aspects of the society of the time: Pauperism, in the city of Prato, and the riots broken out in the time of reforms introduced by Grand Duke Peter Leopold of Habsburg-Lorraine. As a result of several years of work and research, conducted also on experimental fields, the essays of this collection contain the profiles of people and scholars which have been mostly neglected until now: Vannoccio Biringucci, a Sixteenth century scientist from Siena, Aldo Mieli, a prominent international scholar oppressed by fascism, Romualdo Cardarelli, a tireless researcher and unmatched connoisseur of the history of the Tuscany's Presidios. Rich archives of documents, in Italy and abroad, such as Simancas, Kew (London), Paris or Vatican City, as well as the records and documents in Florence, have been mentioned and assessed, getting original and unexpected results. The collection of all these works in a unique volume (which will be followed by other dedicated to the history of ironworks, the Italian revolutionary era, the Napoleonic Era and fascism, anti-fascism and the Italian Resistance), offers a wide range of original interpretations, hints and news to scholars and experts of these themes. First edition: January 2003 - New revised and extended edition: September 2011.