Prince Klemens von Metternich was a German-born Austrian politician and statesman and one of the most important diplomats of his era, serving as the Foreign Minister of the Holy Roman Empire and its successor state, the Austrian Empire, from 1809 until the liberal revolutions of 1848 forced his resignation. His influence on historical developments on Europe has been the subject a numerous assessments. Some of the subjects that has been assessed are Metternich's over-all diplomatic skills and actual degree of influence, his role in shaping the balance of power in Europe, and his opposition to nationalist and liberal movements. Historians agree on Metternich's skill as a diplomat and his dedication to conservatism. According to Arthur May, he believed that: