Ururimi rw’igiswahiri ni rumwe mu ruzahuza abaturage benshi batuye mu Bihugu 5 bigeze Umuryango w’Ibihugu by’Iburasirazuba EAC aribyo u Burundi n’u Rwanda. Nubwo ibyo Bihugu bifite amateka amwe ariko bikaba bitandukanywa n’uburyo byakoronejwe, ibyo bigatuma bivuga indimi zitandukanye cyane cyane icyongereza kivugwa mu Bihugu bitatu byakoronijwe n’abongereza aribyo Uganda, Kenya na Tanzaniya, naho u Burundi n’u Rwanda byakoronijwe n’u Bubiligi bikavuga Igifaransa, usanga ururimi rw’igiswahili ari rwo abaturage benshi abize n’abatize bahuriraho mu buzima bwa buri munsi akaba ari narwo rurimi ruvugwa cyane mu mibanire y’abatuye EAC cyane cyane urwo rurimi rukaba rukoreshwa mu bucuruzi, mu muziki, mu mikino, mu madini n’ahandi, naho igifaransa n’icyongereza bikavugwa mu buzimam mu buyobozi.