Welayta has existed in written form since the 1940s, when the Sudan Interior Mission first devised a system for writing it. The writing system was later revised by a team led by Dr. Bruce Adams. They finished the New Testament in 1981 and the entire Bible in 2002. It was one of the first languages the Derg selected for their literacy campaign (1979–1991). Welaytta pride in their written language led to a fiercely hostile response in 1998 when the Ethiopian government distributed textbooks written in Wegagoda – an artificial language based on amalgamating Wolaytta with several closely related languages. As a result, the textbooks in Wegagoda were withdrawn and teachers returned to ones in Wolaytta.