Rudolf II, Holy Roman Emperor in the context of "Prague, Czech Republic"

Johannes Kepler (27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws of planetary motion, and his books Astronomia nova, Harmonice Mundi, and Epitome Astronomiae Copernicanae. The variety and impact of his work made Kepler one of the founders and fathers of modern astronomy, the scientific method, natural science, and modern science. He has been described as the "father of science fiction" for his novel Somnium.

Kepler was a mathematics teacher at a seminary school in Graz, where he became an associate of Prince Hans Ulrich von Eggenberg. Later he became an assistant to the astronomer Tycho Brahe in Prague, and eventually the imperial mathematician to Emperor Rudolf II and his two successors Matthias and Ferdinand II. He also taught mathematics in Linz, and was an adviser to General Wallenstein.

Prague (/ˈprɑːɡ/ PRAHG; Czech: Praha [ˈpraɦa] ) is the capital and largest city of the Czech Republic and the historical capital of Bohemia. Prague, located on the Vltava River, has a population of about 1.4 million, while its metropolitan area is home to approximately 2.3 million people.

Prague is a historical city with Romanesque, Gothic, Renaissance, and Baroque architecture. It was the capital of the Kingdom of Bohemia and residence of several Holy Roman Emperors, most notably Charles IV (r. 1346–1378) and Rudolf II (r. 1575–1611). It was an important city to the Habsburg monarchy and Austria-Hungary. The city played major roles in the Bohemian and the Protestant Reformation, the Thirty Years' War, and in 20th-century history as the capital of Czechoslovakia between the World Wars and the post-war Communist era.

Ferdinand II (9 July 1578 – 15 February 1637) was Holy Roman Emperor, King of Bohemia, Hungary, and Croatia from 1619 until his death in 1637. He was the son of Archduke Charles II of Inner Austria and Maria of Bavaria, who were devout Catholics. In 1590, when Ferdinand was 11 years old, they sent him to study at the Jesuits' college in Ingolstadt because they wanted to isolate him from the Lutheran nobles. A few months later, his father died, and he inherited Inner Austria–Styria, Carinthia, Carniola and smaller provinces. His cousin, Rudolf II, Holy Roman Emperor, who was the head of the Habsburg family, appointed regents to administer these lands.

Ferdinand was installed as the actual ruler of the Inner Austrian provinces in 1596 and 1597. Rudolf II also charged him with the command of the defense of Croatia, Slavonia, and southeastern Hungary against the Ottoman Empire. Ferdinand regarded the regulation of religious issues as a royal prerogative and introduced strict Counter-Reformation measures from 1598. First, he ordered the expulsion of all Protestant pastors and teachers; next, he established special commissions to restore the Catholic parishes. The Ottomans captured Nagykanizsa in Hungary in 1600, which enabled them to invade Styria. A year later, Ferdinand tried to recapture the fortress, but the action ended in November 1601 with a defeat, due to unprofessional command of his troops. During the first stage of the family feud known as the Brothers' Quarrel, Ferdinand initially supported Rudolph II's brother, Matthias, who wanted to convince the melancholic emperor to abdicate, but Matthias' concessions to the Protestants in Hungary, Austria, and Bohemia outraged Ferdinand. He planned an alliance to strengthen the position of the Catholic Church in the Holy Roman Empire, but the Catholic princes established the Catholic League without his participation in 1610.

Michael the Brave (Romanian: Mihai Viteazul [miˈhaj viˈte̯azul] or Mihai Bravu [ˈbravu]; 1558 – 9 August 1601), born as Mihai Pătrașcu, was the Prince of Wallachia (as Michael II, 1593–1601), Prince of Moldavia (1600) and de facto ruler of Transylvania (1599–1600). He is considered one of Romania's greatest national heroes. Since the 19th century, Michael the Brave has been regarded by Romanian nationalists as a symbol of Romanian unity, as his reign marked the first time in history all principalities inhabited by Romanians were under the same ruler.

His rule over Wallachia began in the autumn of 1593. Two years later, war with the Ottomans began, a conflict in which the Prince fought the Battle of Călugăreni, resulting in a victory against an army nearly three times the size of the army of Michael the Brave, considered one of the most important battles of his reign. Although the Wallachians emerged victorious from the battle, Michael was forced to retreat with his troops and wait for aid from his allies, Prince Sigismund Báthory of Transylvania and Holy Roman Emperor Rudolf II. The war continued until a peace finally emerged in January 1597, but this lasted for only a year and a half. Peace was again reached in late 1599, when Michael was unable to continue the war due to lack of support from his allies. In 1599, Michael won the Battle of Șelimbăr against Andrew Báthory and soon entered Gyulafehérvár (today Alba Iulia, Romania), becoming the imperial governor (i.e. de facto ruler) of Transylvania, under Habsburg suzerainty. A few months later, Michael's troops invaded Moldavia and reached its capital, Iași. The Moldavian leader Ieremia Movilă fled to Poland and Michael was declared Prince of Moldavia. During this period, Michael the Brave changed his seal to represent his personal union of Wallachia, Moldavia, and Transylvania.

Bartholomeus Spranger or Bartholomaeus Spranger (21 March 1546 – 27 June 1611) was a Flemish painter, draughtsman, sculptor, and designer of prints. Working in Prague as a court artist for the Holy Roman emperor Rudolf II, he responded to his patron's aesthetic preferences by developing a version of the artistic style referred to as Northern Mannerism. This style stressed sensuality, which was expressed in smoothly modeled, elongated figures arranged in elegant poses, often including a nude woman seen from behind. Spranger's unique style combining elements of Netherlandish painting and Italian influences, in particular the Roman Mannerists, had an important influence on other artists in Prague and elsewhere, in particular the Dutch Republic, as his paintings were disseminated widely through prints as well as by artists who had worked with him such as Karel van Mander.

The Bocskai uprising, known in Hungary as Bocskai's War of Independence (Hungarian: Bocskai szabadságharc, Bocskai-felkelés) was a revolt which took place in Hungary, Transylvania and modern Slovakia during the Long Turkish War (between 1604 and 1606) against Emperor Rudolf II. The rebel leader was Stephen Bocskai, a Protestant Hungarian nobleman. The Ottoman wars had burdened the Kingdom of Hungary for years, causing famine and disease, and the armies of the Christian states had been weakened by losses to Ottoman and Tatar forces.

Rudolf II persecuted the Protestants, and the wealthy Hungarian noblemen were falsely accused of treason. Bocskai organized the revolt and persuaded the Hungarian military Hajduks to join, defeating the imperial forces and foreign mercenaries. The Hungarian nobility, soldiers and peasants (including the minorities) joined Bocskai's Hajduk army. Although he was supported by the Ottoman Empire, the Crimean Khanate, Moldavia, Transylvania, he prevented an Ottoman siege of Vienna. Bocskai was declared Prince of Transylvania and Hungary, but recognized that total Hungarian independence was impossible against the Habsburg monarchy and the Ottoman Empire. He blazed a political trail for his supporters: the preservation of an independent Transylvania, a potential base for the unification of Hungary. Based on the terms of the Treaty of Vienna in 1606, all constitutional and religious rights and privileges were granted to the Hungarians in both the Principality of Transylvania and Royal Hungary. The treaty also recognized Bocskai as the Prince of Transylvania and guaranteed the right of Transylvanians to elect their own independent princes in the future.

The Brothers' Quarrel (German: Bruderzwist) was a conflict between Rudolf II, Holy Roman Emperor and his brother, Matthias in the early 17th century.

Their other brothers (Maximilian III and Albert VII) and their cousins, especially Ferdinand II and Leopold V, were also deeply involved in the dispute. The family feud weakened the Habsburgs' position and enabled the estates of their realms to win widespread political and religious concessions.

The Imperial Crown of Austria (German: Österreichische Kaiserkrone) is a crown formerly in use by the monarchs of the Habsburg monarchy. The crown was originally made in 1602 in Prague by Jan Vermeyen as the personal crown of Holy Roman Emperor Rudolf II, and therefore is also known as the Crown of Emperor Rudolf II (German: Rudolfskrone). The crown was used as a private crown of the Holy Roman Emperors and Kings of Hungary and Bohemia from the House of Habsburg. In 1804 it became the official crown of the newly constituted Austrian Empire. After 1867 it remained the imperial crown of the Cisleithanian part of the Austro-Hungarian Empire until 1918.