Europe 1812: Build-up to the Russian Campaign

By 1812 Franco-Russian relations had deteriorated, largely because of disagreements over the restoration of Poland, the Continental System against Britain, and the French occupation of Oldenburg. Unable to bend the Russians to his will, Napoleon decided on war. To prepare for the invasion, he occupied Swedish Pomerania and secured military alliances with Prussia and Austria.

Main Events

26–27 Jan 1812 Conquest of Swedish Pomerania

On 19 January 1812 Napoleon ordered Marshal Davout to occupy Swedish Pomerania, both to enforce the Continental System—which Sweden had been lax in enforcing—and to secure the French flank for the invasion of Russia. Without notifying the Swedish government, French troops under General Friant crossed the border on the night of 26/27 January and swiftly took control of the territory.in wikipedia

26 Jan 1812 French departments of Spain

In 1810 Napoleon placed northern Spain under French military governors, giving Catalonia a degree of autonomy in the process. Catalonia’s separation from Spain was cemented in January 1812, when it and Andorra were annexed to the French Empire and reorganized as four French departments: Bouches-de-l'Èbre (prefecture: Lérida); Montserrat (Barcelona); Sègre (Puigcerdà); and Ter (Girona). The annexation became effective on 2 February, but, as it was not officially published, its legal status remained uncertain until it was reversed at the end of 1813.in wikipedia

13 Feb 1812 Battle of Sultanabad

In early 1812 the Persian crown prince Abbas Mirza led a force of as many as 30,000, accompanied by British officers and artillery, across the Araks river in two columns to attack Russian positions in the Caucasus. In February one of the columns encountered a Russian camp of 900 troops at Sultanabad, which it compelled to surrender after inflicting heavy casualties. In the wake of this defeat, the Russians briefly pulled back in the region, until reinforcements arrived later that month.in wikipedia

24 Feb 1812 Treaty of Paris

In late February 1812 the French emperor Napoleon signed the Treaty of Paris with Frederick William III of Prussia, establishing a Franco-Prussian alliance directed against Russia. The alliance allowed French troops to cross Prussia and committed the Prussians to providing 20,842 auxiliary troops—almost half of the 42,000 men the Prussian army was allowed under the Treaty of Tilsit (1807)—to the Grande Armée. Signed under threat of French invasion, the treaty was extremely unpopular in Prussia and prompted the resignation of over 300 Prussian officers, among them the military writer Carl von Clausewitz.in wikipedia

16 Mar–6 Apr 1812 Siege of Badajoz

After securing Ciudad Rodrigo, Arthur Wellesley, Earl of Wellington, moved south with his Anglo-Portuguese Army to attack Badajoz, the other major fortified town on the Spanish frontier, in March 1812. Outnumbering the 5,000-strong French garrison by at least 5 to 1, Wellington besieged Badajoz for 20 days until breaches were made in the walls and an assault could be made. However, French resistance was ferocious and the Allies suffered some 5,000 casualties in just a day’s fighting before the town finally fell.in wikipedia

16 Mar 1812 Franco-Austrian Alliance

In March 1812 the Austrians agreed to supply 30,000 men to support a French invasion of Russia. In return Napoleon guaranteed the integrity of the Ottoman Empire and promised to restore the Illyrian provinces to Austria in exchange for Galicia, which was to be given to a reconstituted Poland.in wikipedia