It is believed that Swahili has been spoken since at least the tenth century. It became a written language in the 16th century. Those who learn to speak Swahili soon realize that a number of the words have an Arabic feel. In fact, at least 20 percent of the words in Swahili are of Arabic origin, while the majority of the remainder are of African origin. Thus, it is not surprising that for several hundred years, Swahili was written with Arabic script.

Krapf was the first to use Roman script instead of the customary Arabic script for writing Swahili. Among the reasons he gave for abandoning the Arabic script were that “the Arabic alphabet would only be an encumbrance on the Europeans” who would later be learning the language and that “the Roman script would make it easier for ‘the Natives in studying European languages.’” The Arabic script continued to be used by some for many years; portions of the Bible were published in it.