On 24 May 1671, the first anniversary of his grandfather Ferdinando II's death, Giovanni Battista Gastone de ' Medici was born in Florence to Grand Duke Cosimo III and Marguerite Louise d ' Orléans.

The child-Grand Duke's regency was bestowed upon Cosimo II's wife and mother, as per his wishes.

Completed around 1623, after the death of Ferdinand's father Cosimo II de ' Medici, Grand Duke of Tuscany, the painting shows Maria Maddalena in the center, with her right hand next to Cosimo II's crown and her left hand resting on her young son's shoulder.

When she was twelve or thirteen, Cosimo I's wife Eleonora of Toledo was outraged because Giulia's riding cloak did not look right ; it was not decorated as she had ordered and it was the wrong length.

Towards the end of 1563 he returned to Italy, conforming to the Roman Catholic Church, and for twelve years, as, his unpublished letters show, was in the service of Isabella de Medici, daughter of the grandduke Cosimo of Tuscany ( not, as Samuel Przypkowski says, in the service of the grandduke himself ).

( Cosimo returns a year later, to the day, in 1434 ).

* September – Cosimo de ' Medici returns to Florence one year, to the day, following his exile by the Alberti and Strozzi faction.

The Florentine chronicler Giovanni Cavalcanti reported that, in the very year of Valla's treatise, Filippo Maria Visconti, Duke of Milan, made diplomatic overtures toward Cosimo de ' Medici in Florence, proposing an alliance against the Pope.

In the same year Guerrazzi was banished to Montepulciano for six months after writing an oration to the memory of Cosimo Del Fante — a native of Livorno who had embraced the ideals of the French Revolution and whom Guerrazzi held up as an example for the idealists of the risorgimento.

The Medici faction gained control of the city in 1434, upon Cosimo de ' Medici's counter coup against the faction that sent him into exile the previous year.

The next year, however, saw a pro-Medici Signoria elected and Cosimo returned.

Cosimo wanted to increase the prestige of the university there and offered a record salary of 1, 800 gold crowns, to become 2, 000 gold crowns after the second year.

Duke Cosimo I de ' Medici confiscated it in the same year, not returning it to the Strozzi family until thirty years later.

He first became associated with the Medici family the year Grand Duke Cosimo II died.

The following year, Susterman completed Maria Maddalena of Austria, Wife of the Grand Duke Cosimo II de ' Medici and Sister of the Emperor Ferdinand, with her son, the Future Ferdinand II, a double portrait of Maria Maddalena and her son, Ferdinand, the future Ferdinando II de ' Medici, Grand Duke of Tuscany.

During Sforza's reign, Florence was under the command of Cosimo de ' Medici and the two rulers became close friends.

Cosimo had endured many crises in his reign, but had managed to cement Medici power over Florence, and in the process became a great patron of the arts.

While not as internationally renowned as the old republic, it bore witness to unprecedented economic and military success under Cosimo I and his sons, until the reign of Ferdinando II, whose reign saw the beginning of the state's long economic decline.

Cosimo experienced several personal tragedies during the later years of his reign.

Cosimo III's reign was marked by a sharp conservative reaction.

Cosimo III commenced his reign with the utmost fervour, attempting to salvage the sinking exchequer and allowing his subjects to petition him for arbitration in disputes.

The name Loggia dei Lanzi dates back to the reign of Grand Duke Cosimo I, when it was used to house his formidable landsknechts ( In Italian: " Lanzichenecchi ", corrupted to Lanzi ), or German mercenary pikemen.

He was also named Console of the prestigious Accademia delle Arti del Disegno of Florence, founded by the Duke Cosimo I, at 13 January 1563, under the influence of Vasari.

Ampelographers find clues about which grape varieties were popular at the time in the writings of Italian writer Cosimo Villifranchi who noted that Canaiolo was widely planted variety in the area along with Sangiovese, Mammolo and Marzemino.

Cosimo de ' Medici was the first Medici family member to essentially control the city from behind the scenes.

Cosimo was succeeded by his son Piero, who was, soon after, succeeded by Cosimo's grandson, Lorenzo in 1469.

Originally published in Latin, the first Italian edition came out in 1546. and the standard Italian edition by Cosimo Bartoli was published in 1550.

Lorenzo's grandfather, Cosimo de ' Medici, was the first member of the Medici family to combine running the Medici bank with leading the Republic.

It was commissioned by Duke Ranuccio I for the visit of Cosimo I de ' Medici.

Pope Innocent VII ( probably1339 – 6 November 1406 ), born Cosimo de ' Migliorati, was briefly Pope at Rome between 1404 and 1406 during the period of the Western Schism ( 1378 – 1417 ) while there was a rival Pope, Antipope Benedict XIII, at Avignon.

The first Pterodactylus specimen was described by the Italian scientist Cosimo Alessandro Collini in 1784, based on a fossil skeleton unearthed from the Solnhofen limestone of Bavaria.

The first pterosaur fossil was described by the Italian naturalist Cosimo Collini in 1784.

Soon after publication, Vesalius was invited as Imperial physician to the court of Emperor Charles V. He informed the Venetian Senate that he was leaving his post in Padua, which prompted Duke Cosimo I de ' Medici to invite him to move to the expanding university in Pisa, which he turned down.

After a late start, he was ordained priest, and Cosimo I de ' Medici, Grand Duke of Tuscany, sent him as an appropriate ambassador to Pope Pius V, a position which he held for fifteen years.

The House of Medici or Famiglia de ' Medici ( ; ) was a political dynasty, banking family and later royal house that first began to gather prominence under Cosimo de ' Medici in the Republic of Florence during the late 14th century.

The grand duchy witnessed degrees of economic growth under the earlier grand dukes, but by the time of Cosimo III de ' Medici, Tuscany was fiscally bankrupt.

The most outstanding figure of the 16th century Medici was Cosimo I, who, coming from relatively modest beginnings in the Mugello, rose to supremacy in the whole of Tuscany, conquering the Florentines ' most hated rival Siena and founding the Grand Duchy of Tuscany.

Henry explicitly stated that he would defend Tuscany from Spanish aggression, but later reneged, after which Ferdinando was forced to marry his heir, Cosimo, to Maria Maddalena of Austria to assuage Spain ( where Maria Maddalena's sister was the incumbent Queen consort ).

Informer Cosimo Capodieci said the SCU used " the Corona because it resembles a crown, meaning the rosary typically used in Church in order to carry out the functions of Jesus Christ and the cross ... Unita because it was necessary to be connected to one another, similar to the rings of a chain.

Building of the palace was begun by Giorgio Vasari in 1560 for Cosimo I de ' Medici as the offices for the Florentine magistrates — hence the name " uffizi " (" offices ").

The project that was planned by Cosimo I, Grand Duke of Tuscany to arrange that prime works of art in the Medici collections on the piano nobile was effected by Francis I of Tuscany, who commissioned from Buontalenti the famous Tribuna degli Uffizi that united a selection of the outstanding masterpieces in the collection in an ensemble that was a star attraction of the Grand Tour.