Born in Kortessem, then in the Spanish Netherlands, now Limburg, Belgium, Lamboy was a member of the Catholic, French-speaking, Walloon nobility.

In 1636, he commanded Imperial troops during a nine-month siege of Hanau, before being forced to retreat, an event still commemorated each June in the Lamboyfest.

Only released from captivity after two years, he returned into the military and campaigned with mixed success as supreme commander of the forces of Elector Ferdinand of Cologne.

[1] His father belonged to the Catholic, French-speaking Walloon nobility loyal to the Habsburg rulers of Spain, and the Holy Roman Empire.

[5] Lamboy's military career began in 1619, when he served under Bucquoy (1571-1621), commander of the Imperial army sent to suppress the Bohemian Revolt.

The Imperial vanguard under Lamboy and the Lorrain army under Duke Charles relieved the Siege of Dole and chased the French besiegers until Dijon.

[9] Pushed back by Bernard of Saxe-Weimar, Lamboy and Lorraine joined forces with Gallas' main army and took part in a futile offensive in late autumn 1636.

[6] Lamboy supported the rebellion of the French nobles Louis, Count of Soissons and Frédéric Maurice, Duc de Bouillon in 1641.

[6] During 1648, Lamboy attacked the Hessian army at their fortress Geseke in March and at Wevelinghoven in June, both times repulsed with heavy losses.

Although he could not prevent the Hessians from taking Düren in September, he outmaneuvered them in October and relieved the Siege of Paderborn one week before the Peace of Westphalia.