Europe 1815: Neapolitan War
Napoleon’s return from Elba destroyed the already tense relations between Murat—both one of Napoleon’s former generals and the King of Naples—and the Austrians. Advancing on the Austrian border, Murat overran the states of central Italy but was unable to break through Austrian defences on the Po. The Austrians then counterattacked in force, chasing Murat from the peninsula and restoring Naples to the King of Sicily.
15 Mar–20 May 1815 Neapolitan War▲
Taking advantage of Napoleon’s return—and already concerned that the Austrians were intent on deposing him—Joachim Murat, the Napoleon-appointed King of Naples, declared war on Austria in March 1815. Despite proclaiming support for Italian independence, Murat was unable to win the other Italian states to his side and instead overran the Papal States, Tuscany, and Modena as he marched on the Austrian border. However, his attempt to cross the Po was repulsed at Occhiobello and, after being decisively defeated at Tolentino, Murat fled to Corsica, leaving his generals to sue for peace.
16 Mar 1815 United Kingdom of the Netherlands▲
In June 1814, in the Eight Articles of London, the European Powers of Britain, Prussia, Austria, and Russia secretly agreed to award the Southern Netherlands (modern Belgium and Luxembourg) to the Sovereign Principality of the Netherlands. This deal was confirmed at the Congress of Vienna in March 1815, on the condition that Sovereign Prince William of the Netherlands cede the Principality of Orange-Nassau and parts of Liège to Prussia. William agreed to these terms and immediately proclaimed himself King of the new united Kingdom of the Netherlands.
20 Mar 1815 Hundred Days begins▲
On 19 March 1815, as Napoleon Bonaparte neared Paris, the French army stationed outside the capital defected to his cause, prompting Louis XVIII to immediately flee for the Netherlands. Napoleon entered Paris the next day, restoring the French Empire. This period of Napoleon’s governance would become known as the Hundred Days, after the approximate length of his reign until his final abdication and Louis’ restoration.
25 Mar 1815 Seventh Coalition▲
Learning of Napoleon’s restoration, the four European Powers—Austria, Britain, Prussia, and Russia—formed the Seventh Coalition against him, with each of the Powers pledging 150,000 troops for the coming conflict. As Britain was unable to field such a number, it agreed to pay subsidies to other European states to make up the shortfall. The coalition was also joined by the other nations partaking in the Congress of Vienna and it was ultimately decided to invade France on 1 July 1815.
5–17 Apr 1815 1815 Tambora eruption▲
In 1815 Mount Tambora, on the island of Sumbawa in the Dutch East Indies, erupted with a Volcanic Explosivity Index of 7—only unambiguously confirmed eruption of that scale since the Lake Taupo eruption in about 180 CE and the largest observed eruption in history. The explosion ejected some 41 cubic kilometers of ash into the air, destroying the village of Tambora and reducing the height of Mount Tambora from 4,300 m to 2,851 m. As a result of the eruption, global temperatures dropped significantly, leading 1816 to be dubbed the Year Without a Summer.
7 Apr 1815 Lombardo-Venetian Kingdom▲
The Treaty of Paris (1814) had confirmed Austrian claims to the territories of the former Lombard Duchy of Milan, which had been ruled by the Habsburg monarchy since 1714. The Congress of Vienna combined this territory with the Austrian-ruled lands of the former Republic of Venice to form the Kingdom of Lombardy–Venetia as a crown land of the Austrian Empire to be ruled in personal union by the Habsburg Emperor of Austria.