May 2, 1866
Peruvian defenders fight off Spanish fleet at the Battle of Callao.
The Battle of Callao occurred on May 2, 1866 between a Spanish fleet under the command of Admiral Casto Méndez Núñez and the fortified battery emplacements of the Peruvian port city of Callao during the Chincha Islands War. The Spanish fleet bombarded the port of Callao (or El Callao), and eventually withdrew without any notable damage to the city structures, according to the Peruvian and American sources; or after having silenced almost all the guns of the coastal defenses, according to the Spanish accounts and French observers.
July 20, 1866
Battle of Lissa – The Austrian Navy , led by Admiral Wilhelm von Tegetthoff, defeats the Italian Navy near the island of Vis in the Adriatic Sea.
The Battle of Lissa (sometimes called Battle of Vis) took place on 20 July 1866 in the Adriatic Sea near the Dalmatian island of Lissa ("Vis" in Croatian) and was a decisive victory for an outnumbered Austrian Empire force over a superior Italian force. It was the first major sea battle between ironclads and one of the last to involve deliberate ramming. The Italian navy fired roughly 1450 shots during the engagement, but failed to do any serious damage to an Austrian ship while losing two battleships. One of the main reasons of this bad performance was due to internal rivalry between the Italian fleet commanders: for example, Italian Vice Admiral Albini, with his group of ships, never participated in the battle. The engagement was made of several small battles: the main was between seven Austrian and four Italian ironclads and showed the ability of Tegetthoff to divide the bigger opponent and destroy the surrounded ironclads left alone.