Mihail Kogălniceanu (Romanian pronunciation: [mihaˈil koɡəlniˈtʃe̯anu] (listen); also known as Mihail Cogâlniceanu, Michel de Kogalnitchan; September 6, 1817 – July 1, 1891) was a Romanian liberal statesman, lawyer, historian and publicist; he became Prime Minister of Romania on October 11, 1863, after the 1859 union of the Danubian Principalities under Domnitor Alexandru Ioan Cuza, and later served as Foreign Minister under Carol I. He was several times Interior Minister under Cuza and Carol. A polymath, Kogălniceanu was one of the most influential Romanian intellectuals of his generation. Siding with the moderate liberal current for most of his lifetime, he began his political career as a collaborator of Prince Mihail Sturdza, while serving as head of the Iași Theater and issuing several publications together with the poet Vasile Alecsandri and the activist Ion Ghica. After editing the highly influential magazine Dacia Literară and serving as a professor at Academia Mihăileană, Kogălniceanu came into conflict with the authorities over his Romantic nationalist inaugural speech of 1843. He was the ideologue of the abortive 1848 Moldavian revolution, authoring its main document, Dorințele partidei naționale din Moldova.

Following the Crimean War (1853–1856), with Prince Grigore Alexandru Ghica, Kogălniceanu was responsible for drafting legislation to abolish Roma slavery. Together with Alecsandri, he edited the unionist magazine Steaua Dunării, played a prominent part during the elections for the ad hoc Divan, and successfully promoted Cuza, his lifelong friend, to the throne. Kogălniceanu advanced legislation to revoke traditional ranks and titles, and to secularize the property of monasteries. His efforts at land reform resulted in a censure vote, leading Cuza to enforce them through a coup d'état in May 1864. However, Kogălniceanu resigned in 1865, following his own conflicts with the monarch.

A decade after, he helped create the National Liberal Party, before playing an important part in Romania's decision to enter the Russo-Turkish War of 1877–1878—a choice which consecrated her independence. He was also instrumental in the acquisition, and later colonization, of Northern Dobruja region. During his final years, he was a prominent member and one-time President of the Romanian Academy, and briefly served as Romanian representative to France.