"Oliver's Army" is a song written by Elvis Costello and performed by Costello and the Attractions, from the former's third studio album Armed Forces (1979).
"Oliver's Army" is a new wave track that was lyrically inspired by the Troubles in Northern Ireland and includes lyrics critical of the socio-economic components of war. Costello had travelled to Northern Ireland and was influenced by sights of British soldiers patrolling Belfast. Musically, the song features a glossy production and a keyboard performance inspired by ABBA, creating a juxtaposition between the lyrics and music that both critics and Costello have pointed out.
Released as the first single from Armed Forces, "Oliver's Army" was Costello's most successful single in the United Kingdom, spending three weeks at number two on the UK Singles Chart and remaining on the chart for 12 weeks. The song also charted in New Zealand, the Netherlands, Ireland and Australia, and it spawned the successful follow-up single "Accidents Will Happen", which reached the top 30 in the UK.
"Oliver's Army" has since been recognised by writers as one of the highlights of Armed Forces and has received critical acclaim for its melody, production, and lyrics.
The song has appeared on numerous rankings of Costello's great songs as well as on multiple compilation albums. It has been covered by multiple artists, including Blur.