Elected as the ruler of Moldavia (Moldova) on January 5/17 1859 and of Wallachia (Tara Romaneasca) on January 24/February 5 1859, colonel A. I. Cuza achieved a de facto union of the two Romanian principalites. The Union was solemnly announced three years later, on January 24/February 5 1862, the new country bearing the name of Romania, with Bucharest as its capital city.
Assisted by his councilor Mihail Kogalniceanu[?], he initiated a series of reforms that contributed to the modernization of Romanian society and of state structures, including:
- The law of monastery fortunes, in 1863
- The Agrarian Reform, 1864
- The Penal Code and the Civil Code, 1864
- The founding of universities in Jassy (1860) and Bucharest (1864).
Cuza was forced to abdicate by the so-called Monstrous coalition formed of conservationists and liberal-radicals. Folowing his overthrow, Charles I of Romania was proclaimed king on 26 March 1881 after a plebiscite.