When interrupted, he violently protested against Italian colonialism while brandishing a scimitar, which led to his arrest and internment in a psychiatric hospital for seven years, until his death.

Zerai's protest, lionized after the end of the Second World War, is considered by Eritrean and Ethiopian historiography as part of the movement against Italian occupation.

[3] On October 6, 1936, Zerai Deres sent a letter to the editor of the Italian newspaper Corriere Eritreo who had written an editorial in which he had asked for the abolition of any form of promiscuity with the "natives".

In return, under carte blanche permission from the Federal Secretary Guido Cortese, many Italian civilians, members of the military, and the paramilitary forces known as the Blackshirts conducted a three-day bloody reprisal in Addis Ababa.

Known in Ethiopia as the Yekatit 12 massacre,[7][8] it resulted in the killing of thousands of people and arrests of many Amhara aristocratic noblemen, about 400 of whom were subsequently deported to Rome, Longobucco, Mercogliano, Ponza, Tivoli, and Asinara, Italy.

During the confrontation, Zerai injured Italian Railways private Vincenzo Veglia, State employee Ferdinando Peraldi, and Infantry Chief Marshal Mario Izzo, who reported very slight[23] wounds that healed within 12 days.

[26] That plan suddenly accelerated when on June 15, 1938, Mussolini was informed that Zerai, who worked as an interpreter for the Ras confined in Rome, had shouted imprecations against Italy and praised Haile Selassie in front of the monument to the fallen of Dogali.

Informed that some people had been severely wounded in attempting to silence Zerai, Mussolini become furious and ordered the total repatriation of all Ethiopian noblemen.

Zerai was arrested, hospitalized at the Umberto I Policlynic, and then taken to Barcellona Pozzo di Gotto (province of Messina, Sicily)[6][28] to the criminal asylum "Vittorio Madia".

[28] Tesfazien also approached the Minister of Foreign Affairs Ambaye Wolde Mariam to present the case to the Imperial Palace, initially without success.

[34] Due to the prevalence of oral tradition, numerous and even contradictory details went to enhance the character, until he became a national folk hero in both Ethiopia and Eritrea, a status he retains to this day.

[45] When the play was staged in Eritrea at Asmara's Opera, Wegayehu Nigatu's interpretation of Zerai was successfully received by the audience and his performance was so convincing that Tesfazien Deres wanted to host the actor for two weeks in order to have the opportunity to converse with him as with his dead brother.

[49] In 1966, when the sculpture of the Lion of Judah was returned to Ethiopia, Emperor Haile Selassie recalled Zerai's patriotic gesture during the re-appointment ceremony held in Addis Ababa.

However, senior members of the war veterans association lobbied for the statue to remain as a symbol of Zerai Deres' sacrifice on behalf of antifascism.

In 2016, on the occasion of the 75th anniversary of the liberation of Addis Ababa from Italian domination, a group of six stamps depicting national heroes, including Zerai, was issued by the Ethiopian Postal Service.