The Habsburg Family Aname Habsburg is derived from the ancestral Castle Habsburg in Aargau, Switzerland. royal German family, one of the principal sovereign dynasties of Europe from the 15th to the 20th century. The Counts of Habsburg are known as early as the 11th century. One of their number became German king, as Rudolf I, in 1273; and in 1282 he bestowed Austria and Styria on his two sons, thus beginning the age-old identification of the Habsburgs with Austria, which they ruled without interruption until 1918, as dukes, archdukes, and emperors. Habs-burgs ruled Hungary and Bohemia from 1526 and retained control over those countries until 1918; Habsburgs also ruled Spain and the Spanish Empire for almost two centuries (1504-06, 1516-1700). In general, the Habsburgs successfully imposed a system of hereditary descent over a widening group of kingdoms that nominally functioned under elective monarchies. Frederick V, the Habsburg king of Germany from 1440, was crowned Holy Roman emperor as Frederick III in 1452; this title remained in the family until the dissolution of the empire in 1806. His son, Maximilian I, through a momentous marriage in 1477, acquired the Netherlands, Luxembourg, Burgundy, and eventually, through his descendants, Spain, Naples, Sicily, and Sardinia as well as New World possessions. The zenith of Habsburg power came under Charles I, king of Spain and emperor (as Charles V) in the 16th century. The dynastic division at Charles's death initiated the Spanish Habsburg line (ruling Spain until 1700) and the Austrian line (known after 1740 as the House of Habsburg-Lorraine), which ruled the Habsburg possessions in central Europe until 1918. Here follows a history of the Habsburg dynasty from its beginnings: in the early years of its existence, the land that was to become Austria was invaded by a series of tribes and armies who traveled along the Danube Valley: the Celts, the Romans, the Vandals, the Visigoths, the Huns, the Avars, the Slavs. In 803, the Babenberger Dynasty was sent to establish a territory in the Danube Valley, known as Ostarrichi, to prevent these invasions. The area became Chris-tianised and predominantly Germanic. The Babenbergers moved their residence to Vienna and controlled Austria for nearly 300 years until Duke Friedrich died childless in 1246, leaving his lands once again vulnerable to warring tribes. By 1278 the Habsburgs had gained control. This mighty dynasty managed to rule Austria up until WW I. Although the Habsburgs were not averse to using a bit of muscle, they preferred less barbaric means of extending their territory; thus Austria gradually expanded thanks to judicious real estate purchases and many politically-motivated marriages. The acquisition of new territories resulted in the Habsburgs - now also the Holy Roman Emperors - ruling much of central Europe, including Hungary, Bohemia and Croatia, parts of Poland, Romania, Bulgaria, Italy, as well as the Netherlands and Spain and its vast overseas possessions. (The Empire was divided into Spanish and Austrian portions in 1556.) In 1571, when religious freedom was granted by the emperor, the majority of Austrians turned to Protestantism. In 1576, the new emperor, Rudolf II, embraced the Counter-Reformation and much of the country reverted, with a bit of coercion, to Catholicism. The attempt to impose Catholicism on Protestant areas of Europe led to the Thirty Years' War, which began in 1618 and devastated much of Central Europe. Peace was finally achieved in 1648 with the Treaty of Westphalia. For much of the rest of the century, Austria was preoccupied with halting the advance of the Turks into Europe. Vienna nearly capitulated to a Turkish siege in 1683 but was rescued by a Christian force of German and Polish soldiers. Austrian forces under General Prince Eugene subsequently swept the Turks to the south-eastern edge of Europe. The removal of the Turkish threat saw a frenzy of Baroque building in many cities, and under the musical emperor Leopold I, Vienna became a magnet for musicians and composers. In 1740, Maria Theresa ascended the throne and ruled for 40 years. This period is generally acknowledged as the era in which Austria developed as a modern state. During her reign, control was centralized, a civil service was established, the army and economy were reformed and a public education system was introduced. However, progress was halted when Napoleon defeated Austria at Austerlitz in 1805. The European conflict continued until the Congress of Vienna in 1814-15. Austria was left with control of the German Confederation but suffered upheaval during the 1848 revolutions and eventual defeat in the 1866 Austro-Prussian War.This led to the formation of the dual monarchy of Austria-Hungary in 1867 under emperor Franz Josef and exclusion from the new German empire unified by Bismarck. A period of prosperity followed but Austria's expansionist tendencies in the Balkans and its annexation of Bosnia-Herzegovina in 1908 led to the assassination of the emperor's nephew in Sarajevo in June 1914 by Serbian separatists. A month later, Austria-Hungary declared war on Serbia, the Russians came to the Serbians? aid and the slaughter of WW I began in earnest. At the conclusion of the war, the shrunken Republic of Austria was created and was forced to recognize the independent states of Czechoslovakia, Poland, Hungary and Yugoslavia which, along with Romania and Bulgaria, had previously been under control of the Habsburgs. The new republic suffered economic strife which led to an upsurge in Nazi-style politics. Austria's embrace of fascism meant that German troops met little opposition when they invaded in 1938 and incorporated Austria into the Third Reich. A national referendum in Austria that year supported the annexation. Austria was bombed heavily in WW II and by 1945 it had been restored to its 1937 frontiers by the victorious Allies. It was divided into four zones by occupying American, British, French and Russian troops who remained entrenched for a decade before withdrawing and allowing Austria to proclaim its neutrality. The republic of Austria was once the center of an empire that stretched across Central Europe and was home to 70 million citizens.