Why did Britain take over the administration of Cyprus in 1878?

Under the Cyprus Convention of 1878, Britain took over the administration of Cyprus to secure a strategic base in the eastern Mediterranean. This move was part of a British guarantee to protect the Ottoman sultan’s Asian possessions against potential expansion by Russia.1

By establishing a presence on the island, Britain aimed to facilitate potential military operations in the Caucasus or Mesopotamia, should they be required to defend Ottoman territories. While the island remained under formal Ottoman sovereignty, the British administration allowed the United Kingdom to exert influence in the region amidst the broader diplomatic challenges posed by the decline of the Ottoman Empire, often referred to as the Eastern Question.12