Zanzibar was a valuable property as the main slave market of the Swahili Coast as well as being a major producer of cloves, and became an increasingly important part of the Omani empire, a fact reflected by the decision of the Sayyid Sa'id bin Sultan, to make it the capital of the empire 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 Omani domains on the Swahili Coast. The other son, Thuwaini, inherited Oman and the Asian domains. Zanzibar's 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 arbitration, Zanzibar and Muscat became two different sultanates.