Bogdan Petriceicu Hasdeu (Romanian pronunciation: [boɡˈdan petriˈt͡ʃejku haʃˈdew] ( listen) 26 February 1838 – 7 September [O.S. 25 August] 1907) was a Romanian writer and philologist, who pioneered many branches of Romanian philology and history.
He was born Tadeu Hasdeu in Cristineştii Hotinului (now Kerstentsi in Chernivtsi Oblast, Ukraine), northern Bessarabia, at the time part of Imperial Russia. His father was the writer Alexandru Hâjdeu, a descendent of the Hâjdău family of Moldovan boyars, with noted Polish connections.
After studying law at the University of Kharkiv, he fought as a Russian hussar in the Crimean War. In 1858 he settled in Iaşi as a high school teacher and librarian. In 1865, Hasdeu published a monograph on Ioan Vodă the Terrible, renaming him for the first time cel Viteaz—"the Brave". The portrayal of this violent, short rule as a glorious moment (and of Ioan himself as a reformer) drew criticism from the Junimea society, a conflict which was to follow Hasdeu for the rest of his life. Still, Hasdeu's version of Ioan's character and his anti-boyar actions were to be reclaimed as a founding myth by Communist Romania.