Almirante Condell is a Duke-class Type 23 frigate in service with the Chilean Navy. It entered service with the Royal Navy in 1991 with the name HMS Marlborough as the sixth ship to bear the name. She was named after John Churchill, 1st Duke of Marlborough, and served in the Middle East. The frigate was taken out of service in 2005 and sold to Chile. The vessel entered service with the Chilean Navy in 2008 and was renamed Almirante Condell after Carlos Condell, a Chilean naval officer during the War of the Pacific. The ship was significantly upgraded from 2020 to 2021 and remains in service.

The Type 23 frigate or Duke class is a class of frigates built for the United Kingdom's Royal Navy. The ships are named after British Dukes, thus leading to the class being commonly known as the Duke class. The first Type 23, HMS Norfolk, was commissioned in 1989, and the sixteenth, HMS St Albans was commissioned in June 2002. They form the core of the Royal Navy's destroyer and frigate fleet and serve alongside the Type 45 destroyers. They were designed for anti-submarine warfare, but have been used for a range of uses. Ten Type 23 frigates remain in service with the Royal Navy, with three vessels having been sold to the Chilean Navy, one being retired in 2021, and two being retired in 2023.