Zanzibar was a valuable property as the main slave market of the Swahili Coast, and became an increasingly important part of the Omani empire, a fact reflected by the decision of the 19th century sultan of Muscat, Sa'id ibn Sultan, to make it his main place of residence in 1837. Sa'id built impressive palaces and gardens in Zanzibar. Rivalry between his two sons was resolved, with the help of forceful British diplomacy, when one of them, Majid, succeeded to Zanzibar and to the many regions claimed by the family on the Swahili Coast. The other son, Thuwaini, inherited Muscat and Oman. Zanzibar influences in the Comoros archipelago in the Indian Ocean indirectly introduced Omani customs to the Comorian culture. These influences include clothing traditions and wedding ceremonies. In 1856, under British direction, Zanzibar and Muscat became two different sultanates.