Born as second son of Wilhelm von Hunolstein († 1607) and Anna Maria von Landsberg († 1636) in
Château-Voué () in the
Duchy of Lorraine, he was initially designated for an ecclesiastical career and studied at
Pont-à-Mousson. His family was an
Hunsrückian knightly house that originated from Castle Hunolstein in
Morbach. In 1614, he was appointed as capitular of
Trier but he resigned his post in 1623 to focus on his military career. His elder brother Jean-Marceloff († 1639) left him the possession of the castle of Château-Voué to administrate it in Johann Wilhelm's absence.
Thirty Years' War Hunolstein joined the army of the
Catholic League at some time, he already held the rank of
captain when he was stationed in the
Münsterland under
Count Anholt in 1623. In the next year, he became chamberlain of the Duke of Lorrain. Two years later, he was promoted to
lieutenant colonel. He gained his own regiment of infantry in 1632. For some years, he campaigned under the exiled Duke
Charles IV of Lorraine. In 1636, Charles appointed Hunolstein to governor of Bouquenom and
Sarrewerden. He switched to the Bavarian army on 2 February 1639 as
Generalfeldwachtmeister but still held close connections to the Duke of Lorraine. In March 1640, Duke Charles named him as governor of
Marsal in Lorraine. His troops fought afterwards in Northern Germany and took part at the capture of
Höxter in autumn 1640. During the Swedish invasion of the
Upper Palatinate in early 1641, he became military commander of
Amberg on 14 January. Two months later, he was recalled to the field army that chased the Swedes under
Johan Banér out of the Upper Palatinate. Hunolstein's regiment was present at the siege of
Neunburg vorm Wald where Banér's rearguard was encircled and brought to capitulation on 21 March. At the same time, he was entrusted by Duke Charles of Lorrain to announce the negotiations between Charles and the French crown to Emperor
Ferdinand III and Elector
Maximilian of Bavaria. Duke Charles who broke relations with
France again after a short period made Hunolstein to governor of
Bitche on 16 July 1641. In 1642, Hunolstein changed to the Imperial army. He and
Adrian von Enkevort were appointed into the
General Staff of the supreme commander
Matthias Gallas in 1643. In January 1644, he led an expedition with 1,000 men to supply the besieged
Magdeburg. He was however caught by the sieging Swedes under
Königsmarck and had to retreat under constant attacks. Hunolstein accompanied Gallas on his
Holstein campaign to support Denmark against the Swedes under
Torstensson in summer 1644. As the Imperial army was forced to retreat and enclosed by the Swedes first at
Bernburg and later in Magdeburg where they run out of food, Hunolstein temporarily thought of leaving the army. In the end, he led the last 1,400 healthy footsoldiers of the army along with 12 field guns and some horsemen safely from Magdeburg over
Wittenberg to
Bohemia in January 1645 while Gallas was fallen ill. It is not clear if Hunolstein participated in the defeat at
Jankau on 6 March as the exhausted infantry of Gallas’ ruined army stayed back at
Prague. On 3 April, he was promoted to
Lieutenant field marshal. His next task was defending the
Danube against the Swedish incursion in
Lower Austria. He prevented all Swedish crossing attempts and managed to recapture the Danube Island at
Krems on 31 May that Swedish troops had taken in March to close the river. However, his following coup on the weak defended Krems failed because Torstensson had sent 1,500 men just in time to reinforce the garrison. Over the following year, Hunolstein took part at recapturing the remaining Swedish strongholds in Lower Austria. From April to May 1646, he commanded the siege works at the reconquest of Krems under the supreme command of Hans Christoph von Puchheim. After the capitulation of Krems on 5 May, the Imperials besieged
Korneuburg. It surrendered after fierce resistance on 4 August to be garrisoned by Hunolstein's regiment. In 1647, he commanded the infantry of the Imperial army under the new supreme commander
Peter Melander, Graf von Holzappel, on the defensive campaign in Bohemia and the following offensive into
Hesse towards
Marburg. On 15 October, Elector Maximilian asked the emperor to leave him Hunolstein for his army to take command of the siege of
Memmingen instead of the Imperial general Enkevort. The emperor allowed Hunolstein's changeover but because Memmingen soon capitulated, Hunolstein stayed into Imperial service as long as Melander needed him. The Imperial army retreated from Hesse in January 1648. Hunolstein with the infantry and
Raimondo Montecuccoli with the cavalry took blocking emplacements behind the
Franconian Saale to repel possible Swedish attacks. In March, Hunolstein changed back to the Bavarian army where he was promoted to
Generalfeldzeugmeister and became teacher to hereditary prince
Ferdinand Maria in military science. He fought at
Zusmarshausen under Jost Maximilian von Gronsfeld. As the latter was deposed and imprisoned by the Elector because of his retreat from the
Lech river following the defeat at Zusmarshausen, Hunolstein became his interim successor as Bavarian commander. He was the only officer that had objected the retreat in the war council, anticipating the Elector's furious reaction. Together with the new Imperial commander
Piccolomini and Johann von Reuschenberg, he defended the river
Inn against the Swedes. Piccolomini put his own infantry under Hunolstein's command to hold the river. The Swedes under
Wrangel failed crossing it in
Wasserburg because of the resistance of the garrison as well as in
Mühldorf because of Hunolstein's defences and the high water-level. As Maximilian of Bavaria did not make Hunolstein but the higher-ranking Adrian von Enkevort the definitive successor of Gronsfeld as his main commander on 2 August, he felt passed over and took his leave from the army.
Later career After the war, Hunolstein returned to his Lorrain estates. But because of his opposition to France throughout the war and his close connections to the exiled Duke Charles, he was expelled from his lands by France in 1654. He found shelter near
Koblenz where he possessed the dominion of Mühlenbach via his wife. In 1655, the Kölner Allianz, a predecessor of the
League of the Rhine as an alliance between the Bishops of
Mainz,
Trier,
Cologne and
Münster as well as the
Duke of Jülich and
Berg, engaged him as commander of their combined forces. However, Hunolstein left this post at the end of the same year because Emperor Ferdinand III offered him to return into his service. The Emperor elevated Hunolstein to the Bohemian
nobility in 1656. He was also made
Freiherr and member of the
Hofkriegsrat. After the Imperials joined
Poland in the
Second Northern War against
Sweden, he was appointed to military commander of
Silesia on 14 July 1657. In 1661, he was allowed to return to his estates at Château-Voué by Emperor
Leopold I. On 13 December 1663, the reinstated Duke Charles of Lorraine acknowledged Hunolstein the possession of the villages
Virming and
Conthil that he had given him before to thank him for his services. He died on 29 July 1664 in
Wrocław. ==Family==