After receiving his early training as a soldier in Rome, attached to the staff of one or other of the Condottieri, young Giovanni was appointed to a military command with the Papal army in Lombardy, when he was little more than out of his teens.  His splendid physique and his prowess in friendly encounter, revealed the lion that was in him.  The leader in all boyish pranks and rivalries, he displayed intrepid courage and unfailing resourcefulness when called upon to prove his metal.  To strike quickly and to strike hard, he knew very well meant the battle half won—­hence there was added to his sobriquet two significant appellations—­“L’Invincible” and “Il Gran Diabolo!”

The troops under his command were, as was the rule in the Papal armies, composed of motley companies of alien mercenaries and forced levies, but, in addition, very many soldiers of fortune, attracted by his fame, rallied to his banner.  Very soon the “Bande Nere,” as Giovanni’s force was called, gave evidence that they had no equals in equipment and efficiency.  Their leader took as his models the infantry of Spain and the cavalry of Germany.  Each man wore a black silk ribbon badge, and each lance bore its black pennon—­hence the “Bande Nere.”

It has been said of Mars, the God of War, that he was susceptible to the wiles of Venus, even when intent on deeds of daring, so, too, was it true of Condottiere Giovanni de’ Medici.  Although born outside the “City of the Lily,” and the child of a non-Florentine mother, he and his were always on terms of good relationship with the gentle Duke Lorenzo.  His associations with Florence were of the closest nature, and “Giovannino” was quite content to look for his bride among the marriageable maidens there.

With an ever open eye to a goodly marriage portion, Messer Giovanni “Il Popolano” viewed the daughters of the Salviati with approval.  That house was famous for its financial prominence—­rivalling that of his own, and Messer Giacopo’s three girls were noted for good looks and clever brains.  Whether love, or money, was the magnet, or whether the two ran together in double harness, young “Giovannino” took tight hold upon the reins, and he and Maria Salviati were betrothed in the autumn of 1517.

To be sure there was a difficulty about the new marital habitation, for a soldier upon active service has no settled home.  Love, however, knows obstacles only to overcome them, and so, somehow or another, the young Madonna brought into the world, one wintry day in February—­it was the nineteenth—­1519, her first-born, a son.  Cosimo they christened him, perhaps after his great ancestor Cosimo “Padre della Patria”—­ “Cosimonino.”  When mother and child could be moved Giovanni sent them, for safety, into Florence, where they were lovingly welcomed by her parents, Messer Giacopo de’ Salviati and his wife Lucrezia, daughter of Lorenzo il Magnifico.