<P> Omani Arab colonisation of the Kenyan and Tanzanian coasts brought the once independent city - states under closer foreign scrutiny and domination than was experienced during the Portuguese period . Like their predecessors, the Omani Arabs were primarily able only to control the coastal areas, not the interior . However, the creation of plantations, intensification of the slave trade and movement of the Omani capital to Zanzibar in 1839 by Seyyid Said had the effect of consolidating the Omani power in the region . Arab governance of all the major ports along the East African coast continued until British interests aimed particularly at securing their' Indian Jewel' and creation of a system of trade among individuals began to put pressure on Omani rule . By the late 19th century, the slave trade on the open seas had been completely strangled by the British . The Omani Arabs had no interest in resisting the Royal Navy's efforts to enforce anti-slavery directives . As the Moresby Treaty demonstrated, whilst Oman sought sovereignty over its waters, Seyyid Said saw no reason to intervene in the slave trade, as the main customers for the slaves were Europeans . As Farquhar in a letter made note, only with the intervention of Said would the European Trade in slaves in the Western Indian Ocean be abolished . As the Omani presence continued in Zanzibar and Pemba until the 1964 revolution, but the official Omani Arab presence in Kenya was checked by German and British seizure of key ports and creation of crucial trade alliances with influential local leaders in the 1880s . Nevertheless, the Omani Arab legacy in East Africa is currently found through their numerous descendants found along the coast that can directly trace ancestry to Oman and are typically the wealthiest and most politically influential members of the Kenyan coastal community . </P> <P> The first Christian mission was founded on 25 August 1846, by Dr. Johann Ludwig Krapf, a German sponsored by the Church Missionary Society of England . He established a station among the Mijikenda on the coast . He later translated the Bible into Swahili . </P> <P> By 1850 European explorers had begun mapping the interior . Three developments encouraged European interest in East Africa in the first half of the 19th century . First, was the emergence of the island of Zanzibar, located off the east coast of Africa . Zanzibar became a base from which trade and exploration of the African mainland could be mounted . By 1840, to protect the interests of the various nationals doing business in Zanzibar, consul offices had been opened by the British, French, Germans and Americans . In 1859, the tonnage of foreign shipping calling at Zanzibar had reached 19,000 tons . By 1879, the tonnage of this shipping had reached 89,000 tons . The second development spurring European interest in Africa was the growing European demand for products of Africa including ivory and cloves . Thirdly, British interest in East Africa was first stimulated by their desire to abolish the slave trade . Later in the century, British interest in East Africa would be stimulated by German competition . </P> <P> In 1895 the British government took over and claimed the interior as far west as Lake Naivasha; it set up the East Africa Protectorate . The border was extended to Uganda in 1902, and in 1920 the enlarged protectorate, except for the original coastal strip, which remained a protectorate, became a crown colony . With the beginning of colonial rule in 1895, the Rift Valley and the surrounding Highlands became reserved for whites . In the 1920s Indians objected to the reservation of the Highlands for Europeans, especially British war veterans . The whites engaged in large - scale coffee farming dependent on mostly Kikuyu labour . Bitterness grew between the Indians and the Europeans . </P>

Discuss the historical development of mapping in kenya
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