The alliance of the three privileged estates was effective for centuries and provided the framework of internal and international relations of Transylvania. After the 18th century, when the danger of Ottoman or Tatar attacks was over, the Union became an alliance of the three estates to protect their vested rights from those who were not represented in the Transylvanian Diet. In the 19th century, the term "three nations" became charged with ethnic considerations, because Romanians were consequently excluded from Transylvanian government.