John Christian of Brieg

Joachim Frederick died on 25 March 1602, leaving his two sons as the heirs of his domains. John Christian had eleven-years and his younger brother George Rudolf had only seven, the regency of the Duchies was taken by their mother, the Dowager Duchess Anna Maria (who held Oława as her dower). After Anna Maria's death in 1605, the regency was taken by the paternal aunt of the young Dukes (and only surviving sibling of the late Joachim Frederick), Elisabeth Magdalena of Brieg and her husband, Charles II of Poděbrady, Duke of Ziębice–Oleśnica.

During some time, John Christian live in Krosno Odrzańskie (German: Crossen an der Oder), where he met his first wife, Dorothea Sybille of Brandenburg.

In 1609 John Christian attained his majority and assumed the government. On 7 October of that year he paid homage to the Emperor Rudolf II in Wrocław. In 1612 his younger brother George Rudolf was formally declared an adult. Then, the brothers decided to make the division of their lands: John Christian retained Brzeg, Oława, Strzelin, Niemcza, Kluczbork and Byczyna, and George Rudolf came into possession of Legnica, Wołów, Złotoryja, Grodźca, Lubin, Prochowice, Wińsko, Wąsosz, Ryczeń and Rudna.

In 1613 John Christian, then a Lutheran, began to profess openly the Calvinism. With him, his younger brother George Rudolf also changed his religion. The brothers followed the example their second-cousin, John Sigismund, Elector of Brandenburg, who shortly before publicly took communion according to the Calvinist rite, after almost two years of professed in secret. Thanks to this, they could renewed the alliance of the Duchy of Legnica-Brzeg with the House of Hohenzollern.

In 1617 Ferdinand II of Habsburg was elected King of Bohemia. The new ruler, raised by the Jesuits, began immediately the Counter Reformation. The Protestants were totally against his election to the Bohemian throne, especially when it became clear that Ferdinand II had no intention to give them the tolerance guaranteed by Imperial Decree of the late Emperor Rudolf II. The conflict between the Bohemians and Ferdinand II deepened when the new King showed his aspirations for the Absolutism rule. In the civil war started between the Bohemians and the Habsburgs, John Christian stood on the Bohemian side. With the insistence of John George of Brandenburg, Duke of Krnov, his brother George Rudolf and his cousins, the Dukes of Oleśnica, Henry Wenceslaus and Karl Frederick of Poděbrady (later his son-in-law) and as General Prefect (Governor) of Silesia (a function held from him since 1617 onwards) he formed an army who, under the leadership of John George of Krnov went to Bohemia to help the insurgents. In 1619 the states of Bohemia announced the dethronement of Ferdinand II, and on 26 July was elected as new King of Bohemia Frederick V, Elector Palatine, a strong Calvinism.

John Christian was a strong supporter of the new King. After the election of Frederick V, he stood at the forefront of the national government of Silesia. On 27 February 1620 in Wrocław the Silesian states paid tribute to Frederick V, during which the formula of the oath was given by the Duke of Brzeg. John Christian also worked in the diplomatic affairs on behalf of King-Elector. In Poland, he sought to raise more troops to support the civil war against the Habsburgs. Also, he made contacts with the Anti-Habsburg opposition in Hungary, where the King counted with the support of Gábor Bethlen, Prince of Transylvania. In Silesia John Christian persuaded several nobles to join to the Anti-Habsburg side, promising military support. However, the cruelty and dictatorial government of Frederick V, the Silesians began to reject the Anti-Habsburg moods and they fading totally on 8 November 1620, when at the Battle of White Mountain were the Habsurg army severely defeated the Bohemian forces. One day after, Prague was occupied by the Habsburgs. Standing all the time faithfully at the side of Frederick V, John Christian urged to the Silesian states to adopt a tax on the continuation of the war. However, the following successful of Ferdinand II between the Princes who support the Elector crashed all his plans; on 23 December John Christian was finally defeated and fled to the court of George William, Elector of Brandenburg. The Silesian government entered immediately in negotiations with the winners. On 28 February 1621 in Dresden, with the mediation of Elector John George I of Saxony, the agreement was signed. The Silesian states sworn fidelity to the Emperor and break completely all relations with his enemies. In addition, Ferdinand II received the sum of 300,000 guilders for participants in the revolt, with the exception of the chief of the Silesian forced, Duke John George of Krnov.

Feared for his life, John Christian went in April 1621 to Frankfurt, in the limits of Brandenburg and granted to him by George William of Brandenburg (who was the nephew of his wife, Dorothea Sybille), where since the end of February the Duke of Brzeg and his family lived. In the meanwhile, the Emperor Ferdinand II give the government of Brzeg to John Christian's brother, George Rudolf. After the subsequent mediation of the Elector of Saxony, on 8 December John Christian could return safely to his Duchy.

In the subsequent years, John Christian wasn't involved in the political game. Nevertheless, he was forced to go into exile again. In 1630 King Gustavus Adolphus of Sweden began his interference in the Thirty Years' War. At his insistence, the Elector John George I of Saxony, until then a faithful follower of the Hasbsburgs, passed to the revolt side. In 1632 the Saxon army entered in the Silesian states, including the Duchy of Brzeg. In the next year, at the Northwestern, came the Imperial army under the command of Hans Ulrich von Schaffgotsch, husband of John Christian's sister, Barbara Agnes. His troops entered in Oława and even took Strzelin, but soon they had to withdraw. Nevertheless, the Imperial Army began to gain advantage and already in the autumn of 1633, Silesia was free from the Anti-Habsburg armies. John Christian was accused of allowing the access of the Saxon armies to Brzeg; the Imperial troops invaded his Duchy, and the Duke, his family and court were forced to fled. First, he moved to Wołów, and shortly after he moved to Wąsosz, where, feared of the troops of Schaffgotsch, and together with his brother, George Rudolf, on 12 October 1633 he managed to come to Poland, stopping in Leszno.

On 20 October 1633 John Christian arrived to Toruń, where he rented a house, after obtaining the prior consent of the King Wladyslaw IV Vasa to move to Poland.

In 1634 John Christian came to Silesia to talk with some Protestant subjects in the duchies and cities. He had the idea to convince the Silesian states to accept the authority of the King of Poland and repudied the overlordship of Ferdinand II; however, this idea was never realized.

John Christian never return to his Duchy of Brzeg. In 1635 Ferdinand II entrusted the government of Brzeg to John Christian's oldest son George III as administrator. In January 1635 John Christian returned to Toruń. On 4 October 1636, and after obtaining the consent of George William of Brandenburg, John Christian assumed the direct administration over Ostróda, where he remained with his family until his death.

John Christian died of pneumonia on 25 December 1639 in Ostróda, six months after his second (morganatic) wife, Anna Hedwig of Sitzsch. Four months later, on 19 April 1640, his body was sent to Brzeg, where he arrived on 1 May. However, the formal funeral took place only less than a year after his death, on 12 December 1640. His body was deposited in the Church of St. Hedwig in Brzeg, alongside his first wife, Dorothea Sybille.