Charles Mathieu Isidore Decaen was a French general who served during the French Revolutionary Wars, as Governor General of Pondicherry and the Isle de France and as commander of the Army of Catalonia during the Napoleonic Wars.

Mauritius, officially the Republic of Mauritius, is an island country in the Indian Ocean, about 2,000 kilometres off the southeastern coast of East Africa, east of Madagascar. It includes the main island, as well as Rodrigues, Agaléga, and St. Brandon. The islands of Mauritius and Rodrigues, along with nearby Réunion, are part of the Mascarene Islands. The main island of Mauritius, where the population is concentrated, hosts the capital and largest city, Port Louis. The country spans 2,040 square kilometres (790 sq mi) and has an exclusive economic zone covering 2,300,000 square kilometres.