Fifteen Years War
Siege of Namur
The Battle of Landensberg by John Wootton
Date 16 March 1710 – 21 August 1725
(15 years, 5 months and 7 days)
Location Europe, North America, South America, Africa, India, Indonesia
Result Treaty of Trier: Second partition of the Spanish Empire, Charles III is proclaimed King of Spain, Augustus II is proclaimed King of Poland-Lithuania
Transfer of territory both European and colonial;
Banner of the Holy Roman Emperor with haloes (1400-1806) Holy Roman Empire

Flag of England England

Statenvlag Dutch Republic
Savoie flag Sicily
Flag of the Kingdom of Prussia (1701-1750) Prussia
Flag of Cross of Burgundy Spain loyal to Charles
Coat of Arms of the Polish-Lithuanian Commonwealth Poland loyal to Augustus
Flag Portugal (1667) Portugal (1718–25)
Flag of Russia Russia (1710–23)
Flag of Denmark Denmark (1710–23)
Flag of Most Serene Republic of Venice Venice (1716–22)

Safavid Flag Safavid Persia (1719–22)

Royal Standard of the Kingdom of France France
Bourbon Spain Flag Spain loyal to Philip
POL COA Wieniawa Poland loyal to Stanisław
Jacobite Standard (1745) Jacobites
Flag of Sweden Sweden (1710–23)
Flag of Bavaria (lozengy) Bavaria (1711–20)
Flag of England Genoa (1713–18)
Flag of the Ottoman Empire (1517-1844) Ottoman Empire (1716–22)
Commanders and leaders
Banner of the Holy Roman Emperor with haloes (1400-1806) Joseph I

Flag of England William III
Flag of England Mary II
Flag of England William IV

Statenvlag Johan Philip

  • Statenvlag Count of Waldeck

Savoie flag Victor Amadeus I
Flag of the Kingdom of Prussia (1701-1750) Frederick I
Flag of the Kingdom of Prussia (1701-1750) Frederick William I
Flag of Cross of Burgundy Charles Habsburg
Coat of Arms of the Polish-Lithuanian Commonwealth Augustus II
Flag Portugal (1667) Marquis of Minas
Flag of Russia Peter the Great

  • Flag of Russia Alexander Menshikov
  • Flag of Russia Fyodor Apraksin

Flag of Denmark Frederick IV
Flag of Most Serene Republic of Venice Geronimo Delphino
Safavid Flag Sultan Husayn

Royal Standard of the Kingdom of France Louis XIV
Royal Standard of the Kingdom of France Louis XV

Bourbon Spain Flag Philip V

  • Bourbon Spain Flag Marquis of Lede
  • Bourbon Spain Flag Count de Gages

POL COA Wieniawa Stanisław I
Jacobite Standard (1745) James Stuart

Flag of Sweden Charles XII

Flag of Bavaria (lozengy) Maximilian II Emanuel
Flag of Bavaria (lozengy) Charles Albert
Flag of England Benedetto Viale
Flag of the Ottoman Empire (1517-1844) Ahmed III

  • Flag of the Ottoman Empire (1517-1844) Nevşehirli Damat Ibrahim Pasha
  • Flag of the Ottoman Empire (1517-1844) Canım Hoca Mehmed Pasha
The Fifteen Years War (1710 - 1725) was a major conflict that involved many of the world's leading powers and affected Europe, North America and South America, as well as parts of Africa, the Middle East, India and Indonesia. Beginning as a war primarily to decide who would sit upon the Polish-Lithuanian throne, the struggle cascaded into a more general conflict between the 'Grand Alliance' of maritime powers (England and the Dutch Republic) and the Holy Roman Empire, against a coalition between the Bourbon kingdoms of Spain and France, alongside their allies.

With the War of the Spanish Succession ending conclusively for the Grand Alliance, several issues still remained in its aftermath, particularly checks on the ambitions of the French king, Louis XIV. In 1709, three years after the end of the previous conflict the French monarchy began to bolster the Swedish-appointed King of Poland-Lithuania, Stanisław I, supporting Swedish soldiers in their campaign to cement the new king's control over his nation, as well as ward off Russian attacks. Fearful of the perceived French-aligned state now lying on his eastern borders, the Holy Roman Emperor Joseph I ordered his armies to sweep into Poland-Lithuania in support of the outed former monarch, Augustus II precipitating a decline in French relations that ultimately led to the outbreak of war in April 1710.

Realizing that both its east and west was open to France and its allies, the HRE hastily resembled their wartime Grand Alliance with the Anglo-Dutch power of William III, their anti-French intervention quickly being met with aggression from Sweden which entered the war on Louis XIV's side later in the year after the declaration of war by Austria on France. With Europe flaring up, a number of alliances in Eurasia were built up over the proceeding 15 years as the armies of almost all major nations clashed on nearly every continent in a drawn out struggle to determine which nations would have influence in the aftermath of the war.

By the height of the war in war in 1720, almost all nations in Europe were at war with the conflict having spread far outside their metropolitan borders to colonies in America, Africa and Asia where the maritime powers found their most success. After a treaty of armistice brought an end to the fighting in the Ottoman-Venetian War and the Great Northern War in 1720 and 1723 respectively, the remaining powers in the Grand Alliance refocused their attentions to soundly defeating France, the maritime powers using their naval power to cripple Louis XV's (the grandson and successor to Louis XIV) navy, whilst the Holy Roman Empire and Prussia invaded over land.

After crushing defeats at the battles of Venisey and Lagesse, Louis XV with the support of his great marshals sued for peace with the powers who were then converging on Paris, however fighting continued for a number of months as Philip V of Spain, King Louis' brother, laid claim to the French throne, receiving the support of several generals in Occitania as his armies merged with those of the marshals who did not wish to give in the Grand Alliance in a last attempt to turn the war in their favour. After successive defeats during his brief occupation of southern France, Philip V was thrown back into Spain and under the threat of invasion, he fled to New Spain, allowing for the heralded return of Charles Habsburg to the Spanish throne.

In July 1725, after fifteen years of constant war, diplomats from the belligerent countries converged on Trier to discuss the terms of the French, Spanish, and Swedish defeats, the parties all agreeing to sign the Treaty of Trier in late August. Granting favourable terms to the members of the Grand Alliance, the treaty recognized several colonial claims of the maritime powers and Portugal, as well as granted vast tracks of territory both European and not, to almost all victorious nations. Furthermore, the nations that signed the treaty recognized Augustus II's claim to Poland whilst partitioning several sq km of its territory to grant to Russia, Prussia and Austria.