Spanish conquest of Sardinia

The Spanish conquest of Sardinia, also known as the Spanish expedition to Sardinia, took place between the months of August and November 1717. It was the first military action between the Kingdom of Spain and the Holy Roman Empire after the War of the Spanish Succession (1701–1714), and was the direct cause of the War of the Quadruple Alliance (1718–1720). The Spanish troops commanded by the Marquis of Lede and Don José Carrillo de Albornoz, 1st Duke of Montemar, supported by the Spanish fleet, defeated the Emperor's troops easily, and conquered the entire island of Sardinia, which had been ruled by the Emperor since the Treaty of Rastatt (1714), returning it again and for the final time to Spain.

Background
After the War of the Spanish Succession, with the Treaty of Rastatt, Spain lost all its possessions in Italy and the Low Countries. The Spanish Netherlands, the Duchy of Milan, the Kingdom of Naples and Sardinia were given to Austria, while Sicily to the Duke of Savoy. These territories had been under Spanish rule for nearly two centuries, and their loss was perceived as a great blow to the country in both practical and prestige terms.

In 1717, with the rise of Spain as an important military power again, and the ambitions of the King Philip V of Spain to regain the Spanish supremacy in Italy and the Mediterranean, the rest of the European powers, Great Britain, France and Austria, to strengthen the Treaty of Utrecht (1713), contemplated ceding Sicily to the Holy Roman Emperor Charles VI, but this arrangement displeased Spain, who wanted to recover the island. With this background, and the arrest in Milan from Spanish Grand Inquisitor, Jose Molina, by the Austrians, Philip V obtained the pretext he sought. In July, the King of Spain, ordered to the Spanish fleet, prepared in Barcelona, conquer Sardinia, initiating hostilities with Austria.

Spanish conquest of Sardinia
The bulk of the Spanish expedition sailed from the port of Barcelona on July 24, and on 30 July, sailed the rest of the fleet. The fleet, under the command of the Marquis de Mari, consisted of 9 ships of the line, 6 frigates, 3 galleys, 2 fireships and 80 transport and merchant ships, and the troops, were composed by 8,500 infantry and 500 cavalry commanded by Don Juan Francisco de Bette, Marquis of Lede.

On 22 August, the Spanish forces landed in Sardinia, and in just two months reconquered the whole island, whose defenses were commanded by the Marquis of Rubi. The quick victory was mainly due to the psychological action of the Marquis of San Felipe, who toured the island by encouraging its inhabitants, who were not happy with the Austrian dominion, preferring to return under the Spanish rule. Only the strengths of Alghero, Aragonese Castle in the Ischia Island, and of the important city of Cagliari resisted, but soon the Austrian troops in Cagliari commanded by Rubi, in the absence of reinforcements, decided to flee to the north of the island, and on 4 October, the Spanish troops took the city. A few days later, on 19 October, the bulk of the Spanish troops led by the Marquis of Lede and the Duke of Montemar laid siege to Alghero, and finally capitulated on 25 October. The last place fell to 30 October, and the Spanish victory was complete.

Consequences
The initial Austrian reaction to this invasion was limited, because Austria had put all their resources on Austro-Turkish War of 1716-18, and the Austrian supreme commander, Prince Eugene of Savoy, wanted to avoid a great war in Italy with Spain. The Treaty of Passarowitz ended the war between the Ottoman Empire and Austria, and on 2 August, this led to the formation of the Quadruple Alliance.

Meanwhile, in July, 1718, the Spaniards, this time with 30,000 men, including four regiments of Dragoons, again led by the Marquis of Lede, and a fleet of 350 ships, and over 250 pieces of artillery, invaded Sicily. The Spanish forces captured Palermo on 7 July, and then divided their army in two. De Lede followed the coast to besiege Messina between 18 July and 30 September, while the Duke of Montemar conquered the rest of the island.

The French, Austrians, and British demanded the Spanish withdrawal from Sicily and Sardinia. The attitude of Victor Amadeus II of Savoy was ambiguous, as he accepted to negotiate with the Spanish Prime Minister, Cardinal Alberoni, to form an anti-Austrian alliance.