British Nationality could be obtained through your birth, or through the birth of any one of your parents or grandparents, in Ethiopia. This arises because of Britain's relationship with Ethiopia and Britain's Colonial history.
To determine what form of British Nationality you might have, an analysis of your family's history must be done, and then applying it to the Nationality laws of Ethiopia that have been passed over the years.
STATUS OF ETHIOPIA
Between 01.03.1852 and 19.04.1942, the Crown exercised extra-territorial jurisdiction in the country.
Thereafter, the country was considered as a foreign country.