The political decision to adopt Swahili as the national and official language of Tanzania has created linguistic and sociolinguistic trends with few parallels in the rest of Africa. Notwithstanding the radical nature of this decision, the choice will be found to be a logical one when viewed in the context of Tanzania’s political and social history and her modern political thought. Various historical, political, religious, and sociocultural factors precipitated a linguistic situation which favoured the emergence of Swahili as an acceptable national language. This paper attempts to make a synoptic review of these factors and a broad examination of the linguistic implications arising from the choice of this language.