During the 10th century, a series of marches were established along the turbulent eastern frontiers of the Holy Roman Empire to secure its borders. In 976 a noble German family, the Babenbergs, was entrusted by Emperor Otto II with a fief located between the rivers Enns and Traisen. The fief that eventually evolved into a duchy, was called Ostarrichi (literally the “Eastern Realm”), and it laid the historical foundations for Oesterreich, or Austria. The Babenberg dynasty ruled their powerful, nearly independent duchy for 270 years.
The Babenbergs often succeeded in keeping out of the wars of their time; they increased their possessions mostly by purchase, gift, treaty or heritage, thus strengthening their political influence and becoming one of the wealthiest rulers of the German Empire. Their marriage politics strengthened them as well: weddings with Byzantine princesses enabled Byzantine influences to penetrate their culture. The connection with the Salisch-Staufisch dynasty of emperors made them one the most powerful families of the German Empire. The Babenbergs moved their place of residence eastwards from Poechlarn and Melk to Tulln, and then to Gars, Klosterneuburg and eventually Vienna (1130). In 1192, the duchy of Steiermark came under Babenberg authority.
The dynasty of the Babenbergs died out in 1246 when Otokar, the King of Bohemia, conquered their territories as well as other countries. King Otokar was defeated in 1278 by the Habsburg Count Rudolf I who had been elected King of Germany. The Habsburgs were to be rulers of Austria for the next 640 years, until the end of World War I.
Despite partitions and fights among brothers for heritage, Austria gained strength and kept adding territories: in 1335 Carinthia and Krain, in 1363 Tyrol, in 1457 Lower Austria, and in 1464 Upper Austria.