Ștefan Mihăileanu was born in 1859, in Beala di Suprã, Ottoman Empire. An ethnic Aromanian, he was one of the first students in Ottoman Macedonia to attend classes in the Aromanian language. Due to the political turmoil that preceded the Macedonian Struggle, Mihăileanu's uncle brought him to Romania, where he continued his education in the Saint Sava National College. The Macedonian Struggle, a series of intertwined cultural, political and military conflicts between the various ethnic and religious communities residing in Macedonia, was to preoccupy Mihăileanu until the end of his life. He combined his career as a teacher and published the Macedonia newspaper between 1888 and 1889. Later on, he continued to produce articles for Peninsula Balcanică (1893–1900). There, he put out proposals on the resolution of the Macedonian Struggle and engaged in controversies with Greek and Bulgarian newspapers. Proposing the slogan "Aromanians by Themselves", he promoted the foundation of churches and schools in Aromanian communities across Macedonia, where a separate Aromanian identity was to be forged. His newspaper was widely distributed in Aromanian communities in Macedonia and even in Thessaly and Epirus. Unlike Greek and Bulgarian activists, he rejected anti-Ottoman irredentism.