Question: Which empire did not see as legitimate the sultan of Zanzibar on the list whose reign started on the 25th of August in 1896 ?

text: List of sultans of Zanzibar
Sultans of Zanzibar

The Sultans of Zanzibar (Arabic: سلاطين زنجبار ) were the rulers of the Sultanate of Zanzibar, which was created on 19 October 1856 after the death of Said bin Sultan, who had ruled Oman and Zanzibar as the Sultan of Oman since 1804. The Sultans of Zanzibar were of a cadet branch of the Al Said Dynasty of Oman. In 1698, Zanzibar became part of the overseas holdings of Oman, falling under the control of the Sultan of Oman. In 1832, or 1840 (the date varies among sources), Said bin Sultan moved his capital from Muscat in Oman to Stone Town. He established a ruling Arab elite and encouraged the development of clove plantations, using the island's slave labour. Zanzibar's commerce fell increasingly into the hands of traders from the Indian subcontinent, whom Said encouraged to settle on the island. After his death in 1856, two of his sons, Majid bin Said and Thuwaini bin Said, struggled over the succession, so Zanzibar and Oman were divided into two separate principalities; Thuwaini became the Sultan of Oman while Majid became the first Sultan of Zanzibar. During his 14-year reign as Sultan, Majid consolidated his power around the East African slave trade. His successor, Barghash bin Said, helped abolish the slave trade in Zanzibar and largely developed the country's infrastructure. The third Sultan, Khalifa bin Said, also furthered the country's progress toward abolishing slavery. Until 1886, the Sultan of Zanzibar controlled a substantial portion of the east African coast, known as Zanj, and trading routes extending further into the continent, as far as Kindu on the Congo River. That year, the British and Germans secretly met and re-established the area under the Sultan's rule.
No Sultan Full name Began rule Ended rule Notes
1 Majid bin Said Sayyid Majid bin Said Al-Busaid 19 October 1856 7 October 1870 Bargash bin Said attempted to usurp the throne from his brother in 1859 , but failed . He was exiled to Bombay for two years
2 Barghash bin Said Sayyid Sir Barghash bin Said Al-Busaid 7 October 1870 26 March 1888 Responsible for developing much of the infrastructure in Zanzibar ( especially Stone Town ) , like piped water , telegraph cables , buildings , roads , etc . Helped abolish the slave trade in Zanzibar by signing an agreement with Britain in 1870 , prohibiting slave trade in the sultanate , and closing the slave market in Mkunazini
3 Khalifa bin Said Sayyid Sir Khalifa I bin Said Al-Busaid 26 March 1888 13 February 1890 Supported abolitionism , like his predecessor
4 Ali bin Said Sayyid Sir Ali bin Said Al-Busaid 13 February 1890 5 March 1893 The British and German Empires signed the Heligoland-Zanzibar Treaty in July 1890 . This treaty turned Zanzibar into a British protectorate
5 Hamid bin Thuwayni Sayyid Sir Hamad bin Thuwaini Al-Busaid 5 March 1893 25 August 1896
6 Khalid bin Barghash Sayyid Khalid bin Barghash Al-Busaid 25 August 1896 27 August 1896 Was a belligerent in the Anglo-Zanzibar War , the shortest war in recorded history
7 Hamoud bin Mohammed Sayyid Sir Hamoud bin Mohammed Al-Said 27 August 1896 18 July 1902 Issued the final decree abolishing slavery from Zanzibar on 6 April 1897 . For this , he was knighted by Queen Victoria
8 Ali bin Hamud Sayyid Ali bin Hamud Al-Busaid 20 July 1902 9 December 1911 The British First Minister , Mr A. Rogers , served as regent until Ali reached the age of 21 on 7 June 1905
9 Khalifa bin Harub Sayyid Sir Khalifa II bin Harub Al-Said 9 December 1911 9 October 1960 Brother-in-law of Ali bin Hamud . Oversaw the construction of harbor in Stone Town and tar roads in Pemba
10 Abdullah bin Khalifa Sayyid Sir Abdullah bin Khalifa Al-Said 9 October 1960 1 July 1963
11 Jamshid bin Abdullah Sayyid Sir Jamshid bin Abdullah Al Said 1 July 1963 12 January 1964 On 10 December 1963 , Zanzibar received its independence from the United Kingdom as a constitutional monarchy under Jamshid