Ayacucho (; ), known as Huamanga () from its creation in 1822 until 1825, is a department of Peru. It is located in the south-central Andes of the country. The region was one of the hardest hit in the 1980s during the guerrilla war waged by Shining Path. It is administered by a regional government. Its capital is the city of Ayacucho.
The department was created by the Reglamento Provisional de Elecciones, published on April 26, 1822, which established the department of Huamanga alongside those of Arequipa, Cuzco, Huancavelica and Puno.
A referendum was held on 30 October 2005, in order to decide whether the department would merge with the departments of Ica and Huancavelica to form the new Ica-Ayacucho-Huancavelica Region, as part of the decentralization process in Peru. The proposal failed and no merger was carried out.
The department is divided into 11 provinces (, singular: provincia), which are composed of 111 districts (distritos, singular: distrito).
The provinces, with their capitals in parentheses, are:
According to the 2007 Peru Census, the language learnt first by most of the residents was Quechua (63.05%) followed by Spanish (36.57%). The Quechua variety spoken in Ayacucho is Chanka Quechua. The following table shows the results concerning the language learnt first in the department by province: