He was born on 13 July 1846 in Lviv in a well-known Lviv family. His father, Stanisław Pilat, was a Polish writer, educator and cultural activist, while his older brother Tadeusz was a lawyer specialising in administrative law, professor and then rector of the University of Lviv, a deputy to the Galician National Parliament and a member of the Academy of Learning in Krakow. In turn, his younger brother Władysław was an economist and sociologist, a professor at the Lviv Polytechnic University and an assistant professor at the University of Lviv. Until 1864, Roman Pilat attended classical high school in Lviv, and then studied law (1864–1866) and philology (1866–1868) at the University of Lviv. In 1869–1871, he first defended his doctorate under the supervision of Antoni Małecki, and obtained an advanced research degree (habilitation) in 1871, becoming an assistant professor at the History of Polish Literature Section. In 1874, he became the head of the Section and the Philological Seminar, and served in those functions until, respectively, 1901 and 1904. After the next two years he became a professor extraordinary, and a full professor in 1880. In the 1880s, he held many important functions, e.g. the Dean of the Faculty of Philology (successively in 1882/1883, 1890, 1895/1896), a correspondent member of the Academy of Learning in Kraków (from 1880), a founding member of the Adam Mickiewicz Literary Society (from 1886, a chairman since 1900), editor of the magazine Pamiętnik Towarzystwa Literackiego im. A. Mickiewicza (1887–1898). A year before his death he received the Order of the Iron Crown of the 3rd class. He died on 6 April 1906 in Lviv. The most important publications by Roman Pilat include O literaturze politycznej Sejmu Czteroletniego, 1788-1792, published in 1872, Ueber das polnische Participium praes. act. auf ‘szy’ (1878), Pieśń Boga-rodzica. I restytucja tekstu pieśni (1879), Początek publicystyki literackiej w Polsce (1882), Jak należy wydawać dzieła polskich pisarzów XVI i XVII wieku (1884), 5 tomowy zbiór spisanych wykładów Historia literatury polskiej (1907–1926) and Gramatyka języka polskiego (1909, two volumes).