Romania, as a country, is rather young. The territory that now makes up Romania was formed when two principalities united: Wallachia and Moldavia. At the time it was a Princedom. There were also many ethnic Romanians living in another country -- the principality of Transylvania.
There was tension because there were also a great number of Hungarians living in Transylvania (and still do) who wanted to unite back with Hungary. This eventually happened in 1940, when Northern Transylvania was returned to Hungary by virtue of the Vienna Awards. At the end of World War II, Romania and all of Transylvania were once again united.
Vlad Tepes Dracula to the Saxons who lived in Transylvania, there is much to see and experience in Transylvania.
Become a Follower of Things about Transylvania, and read In Search of The Lost Ones: The German Soldiers of Transylvania in the Second World War and Their Stories and on Kindle In Search of The Lost Ones: The German Soldiers of Transylvania in the Second World War and Their Stories you can also find it here and here