 However, its sister island Anjouan was preferred by international traders due to its better suitability to large boats, and, for a long time, Mayotte remained poorly developed compared to the three other Comoros islands, often being targeted by pirates and Malagasy or Comorian raids.In 1832, Mayotte was conquered by Andriantsoly, former king of Iboina on Madagascar; in 1833, it was conquered by the neighbouring sultanate of Mwali (Mohéli island in French).On 19 November 1835, Mayotte was again conquered by the Ndzuwani Sultanate (Anjouan sultanate in French); a governor was installed with the unusual Islamic style of Qadi (from the Arabic قاض which means judge).