Conversation so far:
What was significant during the Pre-19th century?
Historically, Afaan Oromo-speaking people used their own Gadaa system of governance.
What type of government did they have?
Oromos also had a number of independent kingdoms, which they shared with the Sidama people.
What were some of their other kingdoms?
Among these were the Gibe region kingdoms of Gera, Gomma, Garo, Gumma, Jimma, Leeqa-Nekemte and Limmu-Ennarea.
Are there any other interesting aspects about this article?
The earliest known documented and detailed history of the Oromo people was by the Ethiopian monk Abba Bahrey who wrote Zenahu le Galla in 1593.

Question: Were they violent people?
Self-contained rewrite: Were Oromo people violent people?