The Capture of Valdivia was a battle in the Chilean War of Independence between Spanish forces commanded by Colonel Manuel Montoya and the Chilean forces under the command of Lord Cochrane, held on 3 and 4 February 1820.

After failing to capture the Spanish fortress of Real Felipe in El Callao, Cochrane decided to assault the city of Valdivia, the most fortified place in South America at the time. Valdivia was considered a threat to Chilean independence as it was a stronghold and supply base for Spanish troops. Valdivia provided a safe landing site for sending reinforcements to the loyalist guerrilla fighting the Guerra a muerte in the area of La Frontera.

Valdivia was isolated from the rest of Chile by native Mapuche territory, and the only entrance to Valdivia was Corral Bay, at the mouth of Valdivia River. The bay was protected by several forts built to prevent pirate raids or any attack from a foreign nation.

The defenses at Valdivia consisted of a number of forts and defensive positions. On the South side of the habour were four forts - Fort Ingles, Fort San Carlos, Fort Amargos and Fort Chorocomayo. Further inland was Corral Castle to defend against a landward assault. On the Northern side was the stone walled Fort Niebla. Mancera Island in the centre of the habour was also heavily garrisoned.

Valdivia (Spanish pronunciation: [valˈd̪iʋja]) is a city and commune in southern Chile administered by the Municipality of Valdivia. The city is named after its founder Pedro de Valdivia and is located at the confluence of the Calle-Calle, Valdivia and Cau-Cau Rivers, approximately 15 km (9 mi) east of the coastal towns of Corral and Niebla. Since October 2007, Valdivia has been the capital of the newly created Los Ríos Region and is also the capital of Valdivia Province. The commune of Valdivia had 140,559 inhabitants (Valdivianos) of which 127,750 lived in the city according to the 2002 census. The main economic activities include tourism, wood pulp manufacturing, forestry, metallurgy, and beer production. The city is also the home of the Universidad Austral de Chile, founded in 1954, and Centro de Estudios Científicos.

The city of Valdivia and Chiloé Island were once the two southernmost enclaves of the Spanish Empire. From 1645 to 1740, the city depended directly on the Viceroyalty of Peru that financed the building of the Valdivian fort system, which turned Valdivia into one of the most fortified cities of the New World. In the second half of 19th century, Valdivia was the port of entry for German immigrants who were given land and settled in the surrounding areas.