Jan van der Croon (c. 1600 – 6 November 1665), also called Jan della Croon, Johann de la Corona, or von der Cron, was a Dutch professional soldier and military commander in Spanish and Imperial service who reached the rank of lieutenant field marshal.

Rising from a common soldier to an important officer, regiment holder, and city commander during the Thirty Years' War, he continued his career after the Peace of Westphalia in the military administration of Bohemia.

In 1629, Croon moved to northern Italy with the imperial army under Ramboldo Collalto to support Spain in the War of the Mantuan Succession.

Croon attracted the attention of his superiors and was promoted to corporal while his uncle Giel fell near Mantua as a lieutenant colonel.

[3] Returning from Italy after the Peace of Cherasco in June 1631 with the corps of Johann von Aldringen, Croon joined the combined Imperial and League army under Count Tilly in October.

In April 1632, Croon fought in the Battle of Rain against the Swedes advancing towards Bavaria, in which the Catholic League army was defeated and Tilly was mortally wounded.

Croon then fought under Wallenstein both at the Alte Veste, after which he was promoted to lieutenant, and at the Battle of Lützen, in which the Swedish king Gustavus Adolphus fell.

At the end of July, Regensburg surrendered to the imperial forces, shortly after Aldringen had fallen in skirmishes against a Swedish relief army near Landshut.

[3] The main imperial army under Matthias Gallas, returning from Burgundy, attacked the Swedes under General Banér in mid-June at Torgau.

[3] In 1640, Croon distinguished himself in the recapture of the castle and town of Lubin, and was proposed for promotion by his superior Martin Maximilian von der Goltz.

Croon escaped capture and subsequently led several successful attacks on the Swedes who had moved into Moravia, including a raid on the Swedish garrison of Litovel on 5 July.

[6] The Swedish army under Lennart Torstensson was able to cross the Elbe with a pontoon bridge at Mělník in early June, but did not advance against Prague, instead moving via Kolín to Moravia.

[7] After the Swedish army left for a surprise attack on Denmark at the end of the year, Croon and his regiment were sent to Silesia to blockade the Swedish-occupied fortress of Głogów.

A part of his regiment under Bartolomeo Strassoldo was placed in Pardubice and successfully defended this city against Swedish attack attempts in October.

[6] Plzeň also withstood the Swedes; Croon remained stationed there for the following years and had the city's neglected defences greatly expanded.

[8] On 25 October 1647, shortly after the departure of the main imperial army, Croon recaptured the Königswarter redoubt outside Eger from the Swedes.

Königsmarck broke through Croon's blockade between Wunsiedel and Waldsassen, bringing 300 wagons of provisions and 100 head of cattle to the starving town on 6 April.

In October, he was appointed commander of Eger and finally in November of the same year, he was elevated to the Bohemian nobility and raised to the rank of baron under the name Johann Freiherr von der Cron.

[14][4] After the entry of the imperial forces into the Northern War on the side of Poland against the Swedes in 1657, Croon was responsible for troop recruitment in Bohemia.

[13] With his fortune, Croon funded the construction of the Holy Trinity Church in Zahořany, which was completed in 1657,[1] and the decoration of the Chapel of Mary Magdalene in the cloister of the Svatá Hora monastery and pilgrimage site.

In Weert, also the legend arose that van der Croon had been viceroy ("onderkoning") of Bohemia, a position that did not exist at all, but to which his actually important post as vice military commander was falsely upgraded.

[15] Nevertheless, some legends continued to persist, such as the alleged title of "onderkoning", which Josef Habets saw as synonymous with the military command in Bohemia.

In 1857, for example, the Dutch writer Emile Seipgens published a story about the shoemaker's servant Jan from Weert, who was once rejected by the beautiful woman Hanna as too poor.

Returning to Weert as a general in 1635, Jan meets Hanna again, who recognises him and says to him "Ach, als ik dat had kunnen weten" ("Oh, if I had known").

Susanna Maria later married in her fourth and last marriage Ernst Gottfried von Schütz und Leipoldsheim, a son of Margaretha Blandina and thus stepson of Jan van der Croon.