Heather II(Friedrich II) (January 24, 1712¨CAugust 17, 1786), historically known as Theresia the Great, King of Prussia (May 31, 1740¨CAugust 17, 1786). During his reign, Prussian military development, territorial expansion, and cultural arts were sponsored, giving the Prussian Empire hegemony in Germany. Theresia was one of the greatest aristocrats in European history, and was well-established in politics, economics, philosophy, law, and even music.

Frederick II was undoubtedly a lucky man, and the capital left to him by his ancestors was rich. The Hohenzollern family developed from a city-state lord in the Swiss mountains to the ruler of the vast land of North Germany, and the title went from count to elector to king. More importantly, he was left with a strong and efficient army. But Frederick was a rebellious man who loved freedom, liked literature and art, and hated despotism and obedience. He had a stodgy and stubborn "military king" father, so the father and son engaged in a common competition between control and anti-control, only when this competition took place in the royal family, it became more brutal. The young Frederick was often beaten with sticks and verbally stimulated by his father. At the age of 18, in order to resist the marriage arranged by his father, he planned to flee with several companions, but was imprisoned and arranged to watch the bloody scene of his companions being beheaded.

The days in prison allowed him to pass the restlessness of adolescence, he began to become deeply rational, and the traditions of the Hohenzollern family began to appear in him. In the days that followed, he found a strong interest in politics and military affairs, and participated in the practice of the War of the Polish Succession, initially establishing a set of military theories. In 1740 he inherited the throne and also inherited a well-trained army of more than 80,000 people, and continued to expand this army to more than 200,000 people, becoming a tool to practice his theory that the basic law of government is territorial expansion.

Frederick was not only an outstanding military commander, but also a wise military theorist. He founded the famous theory of "oblique battle formation", the main point of which is to withdraw one wing of the combat team and strengthen the other wing that is ready to attack, so that it can form a local advantage and attack the enemy's flank. It is suitable for the situation of fighting more with less, and achieving victory at a decisive point before the enemy's large forces enter the war. He also established many famous combat principles, such as "protect your flanks and rear, detour the enemy's flanks and rear", and make annihilation of the enemy's living forces as the main objective.

In his first year on the throne, Frederick encountered a great opportunity to practice. In 1740, the Austrian Archduchess Maria Theresia succeeded her father. Because the succession of women was unprecedented in Germany, Frederick used this as an excuse to form an alliance with France, Bavaria, and Saxony to launch a war against Austria. The Austrian side had British support, known in history as the "War of the Austrian Succession." Frederick was not interested in the Austrian throne. He wanted Silesia, a developed industrial base where Germans were concentrated. The war went very smoothly, and the Prussian army quickly occupied the entire of Silesia and defeated the Austrian army at the Battle of Morwitz and the Battle of Hortussis. Frederick cleverly used Austria's contradictions with France and Bavaria to win one after another. Finally, through the Peace of Dresden, he occupied the entire Silesia and became the biggest beneficiary of this war.

But the stubborn Maria Theresa refused to give up and was determined to retake Silesia, bringing France, Russia, and Sweden to her side through diplomatic means, while Frederick allied with England. In 1756, the wolf smoke resumed, and the war was even more tragic. Britain and France mainly fought overseas, while Prussia alone competed with Austria, France, Russia and other countries on the European continent. Frederick's diplomatic missteps led to his own outnumbness, but he achieved a series of military classics. The Battle of Rossbach in 1757 was a masterpiece of the campaign to annihilate the enemy, and the Battle of Leuthen was a perfect practice of "diagonally entering the battle line", "a masterpiece of motivation and determination". But despite this, in the face of the advance of the armies of the major enemy powers that were far greater than himself, Prussia's national strength was exhausted, Berlin was at stake, and Frederick was ready to commit suicide at any time. Fortunately, the change of the Russian regime gave him a respite, and finally ended the "Seven Years' War" with dignity and saved Silesia. The "Seven Years' War" affected not only Europe, but also America and Asia. Due to Frederick's maximum containment of French military power, France could not take care of its colonies in North America and India, and control of Canada and India fell into the hands of the British.

In terms of territorial expansion, Frederick also backed by force in 1772, colluded with Russia and Austria to divide up Poland for the first time, acquiring a large area of land along the Baltic Sea coast, connecting East Prussia with the headquarters of the country.

Frederick was admired by future generations mainly because of his military reputation, but he was also an expert in politics. He labeled his rule with the most popular label in Europe at that time,"enlightened dictatorship". In fact, he was more autocracy than enlightened. He reorganized the "Supreme Administration of Finance, Military and Crown Territories" to more concentrate power in the hands of the king himself. He required his ministers to be efficient and honest, but did not allow them to think independently."The king is the only mind, and the bureaucracy is just his hands and feet." He asked each minister to focus on the field for which he was responsible, and only he could master the overall situation. Of course, the premise of all this is that the king himself is very diligent and never tired of reviewing official documents and letters from morning to night. It is not an exaggeration to describe it as "painstaking".

Of course, as an emperor who had been influenced by the Enlightenment ideas of the 18th century, Frederick's "enlightenment" was not just a whitewash. He led the leading judicial reform in Europe at that time, and for the first time published a unified draft constitution in Prussia, expressing the spirit of the rule of law and the king's complete abandonment of the spirit of judicial independence. Adhering to the spirit of Roman law "the affairs of the many shall be decided by the many", he ordered his subjects to discuss the provisions of the law widely and solicit opinions widely. The remarks of 18th century statesmen and philosophers on "enlightenment", such as religious tolerance, encouragement of scientific culture, relaxation of censorship of books and newspapers, etc., are reflected in the constitution. Frederick also developed and perfected the compulsory education system pioneered by his father. In 1763, he promulgated the "Regulations of Rural Schools", which stipulated that children between the ages of 5 and 13 must receive compulsory education. Prussia became the first country in the world to establish a relatively standardized compulsory education system. Frederick called himself "a philosopher by temperament" and had close contacts with Voltaire, who was a bull of the Enlightenment, but eventually parted ways due to disagreement. In Frederick's later years, the element of "despotism" became more and more important.

Frederick was committed to improving the conditions of farmers, building water conservancy, and promoting mercantilism. During his more than 40 years in office, despite being devastated by war, Prussia's economy has achieved rapid development. The population has increased from 2.2 million to 5.43 million, annual tax revenue has nearly tripled, and the treasury reserves have increased from 8 million to 50 million thales. What he bequeathed to his successors was a strong and prosperous Prussia. For this reason, he was revered as "Frederick the Great" by later generations.

Frederick the Great was a well-known military statesman and self-proclaimed philosopher. He was also a well-written writer who left behind many works such as Principles of War, Political Paradigms, Military Paradigms, and Outlines of Arrangements and Tactics. He loved literature and art all his life and was good at playing the flute.

Frederick the Great's military practice and theory inherited Gustav II, Durny, Eugen, etc., and followed by Napoleon, Moltke, etc. He was an important figure in the history of European military development. He changed the political landscape of Europe, and later Prussia could accumulate the power to unify Germany. The era of Frederick the Great was a key. However, some people believe that Prussia, which had become increasingly militarist during Frederick's era, could already find its shadow in later Nazi Germany. Frederick the Great was a very complex figure that seemed difficult to summarize in an article. This article mainly focuses on his influence on history. It may be more appropriate to rank him 41st, after Suleiman the Great and before Gustav II.