The Church of the Holy Trinity was founded by Emperor Menelik II soon after he moved his imperial capital from Mt. Entoto to Addis Ababa. The original church, built of wood with intricate carvings, was constructed with the help of artists from India. Located close to the Imperial Palace, it was frequently visited by the royal family.
In 1928, a cornerstone was laid by Empress Zewditu for a new cathedral to be built. Work progressed slowly and was halted during the Italian occupation of 1936 to 1941. The new Cathedral would not be completed until 1942, after the return from exile of Emperor Haile Selassie following the Italian occupation.
Trinity was made the burial ground for those who fought against the Italians both inside the country and in exile. No other persons, other than high clergy, are allowed to be buried on the grounds of the Cathedral itself (although there are a public cemetery and a public masoleum behind it). Emperor Haile Selassie built a mausoleum for his family in the crypt under the Cathedral, and the Imperial family continue to use it as their tomb.
Trinity Cathedral has been the site of many great church and state ceremonies, including the enthronements of the Patriarchs of the Ethiopian Orthodox Church and the consecration of all Archbishops and Bishops.