After the defeat of the Third Coalition and the consequent Treaty of Pressburg, on May 1, 1806, the Kingdom of Italy had been given by Austria the eastern and remaining part of the Venetian territories, including Istria and Dalmatia down to Kotor (at this time called Cattaro), even if it has to give Massa and Carrara to Elisa Bonaparte's Principality of Lucca and Piombino.

The Duchy of Guastalla is annexed on May 24.

Italy cedes Monfalcone to Austria and gains Gradisca by the Convention of Fontainebleau with Austria of October 10, 1807, putting the new border on the Isonzo River.

The conquered Republic of Ragusa is annexed in spring 1808 by general Marmont.

This is the only time in modern history that Ragusa is united to Italy.

On April 2, 1808, following the dissolution of the Papal States, the Kingdom annexes the present-day Marche.

At its maximum extent, the Kingdom has six million seven hundred thousand inhabitants and is composed by two thousand one hundred and fifty-five communes.

The final arrangement of the Kingdom of Italy arrives after the new defeat of Austria: Emperor Napoleon and King Maximilian I Joseph of Bavaria sign the Treaty of Paris on February 28, 1810, deciding an exchange of territories involving Italy also.

Bavaria cedes southern Tirol to the Kingdom of Italy, which in its turn cedes Istria and Dalmatia (with Ragusa) to France, incorporating the Adriatic territories into newly created the French Illyrian Provinces.

Small changes to the borders between Italy and France in Garfagnana and Friuli come in act on August 5, 1811.

In practice, the Kingdom is a dependency of the French Empire.

The Kingdom serves as a theater in Napoleon's operations against Austria during the wars of the various coalitions.

Trading with the United Kingdom is forbidden.

Eugène de Beauharnais, lined up the Mincio River with his army against the German invasion When Napoleon abdicates to both the thrones of France and Italy on April 11, 1814, attempts to be crowned king.

The Senate of the Kingdom is summoned on April 17, but the senators show themselves undecided in this chaotic situation.

When a second session of the assembly takes place on April 20, the Milan insurrection foils the Viceroy's plan.

In the riots, finance minister Count Giuseppe Prina is massacred by the crowd, and the Great Electors disband the Senate and call the Austrian forces to protect the city, while a Provisional Regency Government under the presidency of Carlo Verri is appointed.

Eugène surrenders on April 23, and is exiled to Bavaria by the Austrians, who occupy Milan on April 28.

On April 26, the Empire appoints Annibale Sommariva as Imperial Commissioner of Lombardy, while many taxes are abolished or reduced by the Provisional Regency.

Finally, on May 25, the Supreme Imperial Commissioner Count Heinrich von Bellegarde takes all the powers in Lombardy, and former monarchies in Modena, Romagna and Piedmont are gradually re-established; on May 30, the Treaty of Paris is signed, and the remains of the kingdom are annexed by the Austrian Empire, as will be announced by Count Bellegarde on June 12.