Early years
He was born in Berlin, the son of Frederick William I, the so-called "Soldier-King," who created a formidable army and efficient civil service. His mother was Sophia Dorothea of Hanover (1687–1757). Unlike her husband, Sophia was well-mannered and well-educated. His maternal grandfather, George, Elector of Hanover, was the heir of Queen Anne of Great Britain, whom George succeeded in 1714, as King George I of Great Britain.

At the time of Frederick's birth, the Houses of Brandenburg and Hanover were enjoying great prosperity; the birth of Frederick was welcomed by his grandfather with more than usual pleasure, as two of his grandsons had already died at an early age. Frederick William wished his sons and daughters to be educated not as princes and princesses, but as children of simple folk. He had been educated by a French-woman, Madame de Montbail, who later became Madame de Rocoulle, and he wished that she should educate his children. Frederick was brought up by Huguenot governesses and tutors and learned French and German simultaneously.

As Crown Prince, Frederick displayed passionate interests in French literature, poetry, philosophy, and Italian music. This roused the suspicions of his father, who wanted to see his son follow more "masculine" pursuits like hunting and riding. He called his son "an effeminate chap," and subjected him to bloody and humiliating beatings. When he was 18, Frederick plotted to flee to England with a group of friends, all junior army officers. But he botched his escape, and was arrested with friend (and possibly lover) Hans Hermann von Katte. An accusation of treason was leveled against both the prince and Katte since they were officers in the Prussian army and had tried to flee from Prussia, allegedly even having hatched a plan to ally with Britain against the Prussian king. The prince was threatened with the death penalty, and the king did not rule out an execution. The proud prince had to submit to his father's demands. Frederick was forced to watch the execution by decapitation of his friend Katte on November 6, 1730, and was strictly supervised in the following years.

Frederick the GreatThe only way that Frederick atoned (and regained his title of crown prince) for this in his father's eyes was in his marriage to Elisabeth Christine von Braunschweig-Bevern on June 12, 1733. The involuntary matrimony did not lead to children as after becoming king, Frederick mostly ignored his wife. While Voltaire indicated that Frederick was homosexual, there is no clear evidence of his having shown such behavior.

After the crisis in the relationship with the King in the early 1730s, father and son made a chilly peace in the late 1730s. Frederick William gave his son the chateau Rheinsberg north of Berlin. In Rheinsberg Frederick assembled a small number of musicians, actors and other artists. He spent his time reading, watching dramatic plays, making and listening to music, and regarded this time as one of the happiest of his life.

The works of Niccolò Machiavelli, such as The Prince, were considered a guideline for the behavior of a king in Frederick's age. In 1739, Frederick finished his "Antimachiavel, ou Examen du Prince de Machiavel" - a writing in which he opposes Machiavelli. It was published anonymously in 1740 but apparently disseminated by Voltaire.

Kingship
As king, Frederick did not have a vision for a unified Germany; this had to wait until Bismarck planned the wars of unification a century later. Frederick's goal was to improve his country of Prussia. Toward this end he fought his wars mainly against Austria, whose Habsburg dynasts reigned as emperors of the Holy Roman Empire almost continuously from the 15th century until 1806). Frederick established Brandenburg-Prussia as the fifth and smallest European great power by using the resources his father had made available. For 100 years the ensuing Austro-Prussian dualism made a unified Germany impossible until Prussia's defeat of Austria in 1866.

Frederick led the Prussian forces during the War of the Austrian Succession (1740-1748), during the Seven Years' War (1756-1763), and in the War of the Bavarian Succession (1778) - not only as king, but also as the military commander in the field. He was quite successful on the battlefield; Frederick is often admired as one of the greatest tactical geniuses of all time. Even more important were his operational successes, especially preventing the unification of superior enemy armies and being at the right place at the right time to keep enemy armies out of Prussian core territory.

Frederick managed to better Prussia from being a European backwater and make it an economically strong and politically reformed state. His acquisition of Silesia was orchestrated so as to provide Prussia's fledgling industries with raw materials, and he protected these industries with high tariffs and minimal restrictions on internal trade. Canals were built, swamps were drained for agricultural cultivation, and new crops, such as the potato and the turnip, were introduced. With the help of French experts, he reorganized the system of indirect taxes, which provided the state with more revenue than direct taxes. He abolished torture and granted wide religious freedom (although he himself did not care much for religion). He gave his state a modern bureaucracy whose mainstay until 1760 was the able War and Finance Minister Adam Ludwig von Blumenthal, succeeded in 1764 by his nephew Joachim who ran the ministry to the end of the reign and beyond. The civil service code was based on respect for law and ethics, as well as pride in one's profession. This legacy was passed on into the modern German state and is a main reason why he is still admired as a historical figure within Germany. A major example of the place that Frederick holds in history as a ruler is seen in Napoleon Bonaparte, who saw Frederick as the greatest tactical genius of all time.

Having no children of his own, Frederick was succeeded by his nephew as King Frederick William II of Prussia.

Music, arts, and learning
Frederick was a gifted musician. He played the cross-flute and composed one-hundred sonatas for the flute as well as four symphonies. His court musicians included C. P. E. Bach, Johann Joachim Quantz, and Franz Benda. A meeting with Johann Sebastian Bach in 1747 in Potsdam led to Bach writing The Musical Offering.

He also aspired to be a philosopher-king like the Roman emperor Marcus Aurelius. He stood close to the French Enlightenment and admired above all its greatest thinker, Voltaire, with whom he corresponded frequently. Their personal friendship, however, came to an unpleasant end after Voltaire's visit to Berlin and Potsdam in 1750-1753.

Frederick the Great invited Joseph-Louis Lagrange to succeed Leonhard Euler at the Berlin Academy.

In addition to his native language, German, he spoke French, English, Spanish, Portuguese, and Italian; he also understood Latin, ancient and modern Greek, and Hebrew. Later in his life, he learned Basque, Slavic, and Chinese.

Legacy
Frederick had famous buildings constructed in his chief residence, Berlin, most of which still exist today, such as the Berlin State Opera, the Royal Library (today the Staatsbibliothek zu Berlin), St. Hedwig's Cathedral, the French and German Cathedrals on the Gendarmenmarkt, and Prince Henry's Palace (now the site of Humboldt University). But the king preferred spending his time in his summer residence Potsdam, where he built the palace of Sanssouci, the most important work of Northern German rococo.

To this day Frederick remains a controversial figure in Germany and Central Europe. He called himself the "first servant of the state", but the Austrian empress Maria Theresa called him "the evil man in Sanssouci." He was both: an enlightened ruler and a ruthless despot. Through reform, war, and the first Partition of Poland (1772), he turned his state of Brandenburg-Prussia into a European great power.

Frederick did not believe in the Divine Right of Kings and would often wear old military uniforms unlike the exaggerated French style. He merely believed the crown was "a hat that let the rain in".

Economy
During the reign of Frederick the II, the effects of the Seven Years War and the gaining of Silesia greatly changed the economy. The circulation of depreciated money kept prices high. To revalue the Thaler, the Mint Edict of May 1763 was proposed. This stabilized the rates of depreciated coins that would be accepted and provided for the payments of taxes in currency of prewar value. This was replaced, in northern Germany by the Reichsthaler, worth one-fourth of a Conventionsthaler. Prussia used a Thaler containing one fourteenth of Cologne mark of silver. Many other rulers soon followed the steps of Frederick in reforming their own currencies-- this resulted in a shortage of ready money.

Chronology
The following chronology of events took place during his life:

1740 May 31: Death of the King Frederick William
1740 October 20: Death of the Emperor Karl VI.; The War of the Austrian Succession begins
1741 April 10: Battle of Mollwitz
1742 June 11 and July 28: Separate peace treaties with Austria; Silesia becomes part of Prussia
1744 August 10: War breaks out again with Austria
1745 December 25: Peace. Prussia and Frederick have won all 5 battles against Austria in the two Silesian Wars
1748 Austrian war ends.
1756-1763 Seven Years' War. Frederick is confronted with an Austrian-French-Russian-Saxon alliance. Afraid of being attacked by a resentful Austria, he decides to take the initiative. Initial successes against Saxony and Austria in 1756-1757 are not severe enough to reach a conclusive decision. The Prussians have to retreat from Bohemia. For the rest of the war, Frederick is busy trying to defend the triangle of Berlin - Silesia - Saxony. In the west Prussia is sheltered by Britain-Hanover from France. Defence in Northern and Eastern Prussia is only sporadic.
1757 June 6: First defeat of Frederick in the Battle of Kolin
1757: Frederick wins his greatest victory at the Battle of Leuthen against Prince Charles of Lorraine
1758 August 25: Victory against superior Russian troops at the Battle of Zorndorf.
1759 August 12: Disastrous defeat of Frederick and his army in the Battle of Kunersdorf
1762 Armistice and peace with Russia; Austria is financially ruined
1763 Prussia neither gains nor loses territories
After the war Frederick begins immediately to rebuild his country.
1772 Prussia and Austria join Russian intervention in Poland's War of the Confederation of Bar, resulting in the first of the three Partitions of Poland. By seizing northwestern Poland, Prussia instantly gains control over 80% of Poland's total foreign trade. Through levying enormous custom duties on Polish trade using this route, Prussia accelerates the inevitable collapse of Poland (Encylcopaedia Britannica.)
1778 After the death of the Bavarian Kurfürst (elector) Austria tries to annex Bavaria. Frederick (aged 66) invades Bohemia. Austria has to give in.
1781 Frederick publishes his Essay on the Forms of Government, a recipe for efficiency in absolute governments.
1786 August 17 Frederick II dies.