First Italo-Ethiopian war
However, the bilingual [Treaty of Wuchale] did not say the same thing in Italian and Amharic; the Italian version did not give the Ethiopians the "significant autonomy" written into the Amharic translation. The Italian text stated that Ethiopia must conduct its foreign affairs through Italy (making it an Italian protectorate), but the Amharic version merely stated that Ethiopia could contact foreign powers and conduct foreign affairs using the embassy of Italy. Italian diplomats, however, claimed that the original Amharic text included the clause and Menelik knowingly signed a modified copy of the Treaty. In October 1889, the Italians informed all of the other European governments because of the Treaty of Wuchale that Ethiopia was now an Italian protectorate and therefore the other European nations could not conduct diplomatic relations with Ethiopia. With the exceptions of the Ottoman Empire, which still maintained its claim to Eritrea, and Russia, which disliked the idea of an Orthodox nation being subjugated to a Roman Catholic nation, all of the European powers accepted the Italian claim to a protectorate.
More details are in the article. In brief after the Ethiopian Emperor Menelik II realized he had been deceived into signing away his country's sovereignty, he repudiated the treaty, and the Italians went to war.
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