During the first century A.D., Roman Emperor Trajan's legions made their way across the Danube into Dacia, a land inhabited by the Dacians. A part of the Dacia's territory was made into a Roman province, after being conquered by the Romans. The territory received the name "Dacia Felix." Roman rule lasted for about 165 years. The Romanian nation was born of the ethnic mix of Romans and Dacians.
Successive waves of invaders came across Dacia after the Roman withdrawal during the reign of Aurelian (271). The Hungarians arrived in the ninth century. 
One of Romania's most interesting leaders was Vlad III, Prince of Wallachia called "Vlad the Impaler" AKA:  Drachula. He reined from 1448 to 1476 and was best known for his cruelty of impaling criminals and invaders to scare off the Turks.
In 1526 the Turks took control over the territory of the former Hungarian Kingdom, Transylvania, Moldavia and Walachia became autonomous principalities, although they were forced to recognize the supremecey of the Ottoman Empire, to which they paid a tribute.
During the Russo-Turkish War of 1828 - 1829, Russian troops led by Pavel Kiseleff occupied Moldova and the Romanian Land (until 1834). Between 1812 and 1918, the Moldavian province of Bessarabia was annexed by Russia. After the defeat of Russia in the Crimean War (1853-1856), the Romanian principalities came under the protection of the seven powers who signed the Paris Peace Treaty.
After the Second World War, Romanian territory was occupied by Soviet Troops until 1958. The period in which Nicolae Ceausescu was in power (1965-1989) was devastating for Romania. His dictatorship was deposed in 1989, following widespread popular anticommunist uprisings.
In March 2004, Romania became a member of NATO and in 2007 a member of the European Union.