Battle of Gembloux ( 1578 ) The Battle of Gembloux took place at Gembloux , near Namur , Low Countries , between the Spanish forces led by Don John of Austria ( " Spanish : Don Juan de Austria " ) , Governor - General of the Spanish Netherlands , and a rebel army composed by Dutch , Flemish , English , Scottish , German , French and Walloon soldiers under Antoine de Goignies , during the Eighty Years ' War and the Anglo - Spanish War ( 1585 – 1604 ) . On January 31 , 1578 , the Spanish cavalry commanded by John ' s nephew , Don Alexander Farnese , Prince of Parma ( " Spanish : Alejandro Farnesio " ) , after pushing back the Dutch cavalry , attacked the Netherlandish army , causing an enormous panic amongst the rebel troops . < ref name = " Colley Grattan . Holland p . 113 " / > The result was a crushing victory for the Spanish forces . The battle hastened the disintegration of the unity of the rebel provinces , and meant the end of the Union of Brussels . Prelude . After the terrible Sack of Antwerp by Spanish mutineers on November 4 , 1576 , Catholics and Protestants of the Low Countries concluded the Pacification of Ghent , to remove all Spanish troops . The Spanish Tercios were in fact withdrawn to Italy in April 1577 , after that the new Governor - General of the Spanish Netherlands , the famous Christian knight , and half - brother of Philip II of Spain , Don John of Austria ( victor of Lepanto ) , had signed the Perpetual Edict . However , in the summer of 1577 , Don John of Austria ( brandishing the motto " In hoc signo vici Turcos , in hoc vincam haereticos " ) began planning for a new campaign against the Dutch rebels , and in July , 1577 , he took by surprise the Citadel of Namur without a fight . This action further destabilized the uneasy alliance between Catholics and Protestants . From December 1577 , John of Austria , still based in Luxembourg , received reinforcements from the Spanish Lombardy . Some 9 , 000 battle - hardened Spanish troops under Don Alexander Farnese , Prince of Parma ( Duke after the death of his father , Ottavio Farnese , Duke of Parma , in September 1586 ) , complemented by 4 , 000 troops from Lorraine under Peter Ernst , Count of Mansfeld , and local Walloon troops from Luxembourg and Namur . By January 1578 , he had between 17 , 000 and 20 , 000 men at his disposal . The Union of Brussels had 25 , 000 men - at - arms , but these troops were badly equipped and led , and above all very divers : Dutch , Flemish , English , Scottish , Walloon , German and French , and religiously ranging from staunch Catholics to zealous Calvinists . < ref name = " Colley Grattan . Holland p . 113 " / > Battle of Gembloux . In the last days of January 1578 , the Netherlandish army was camped between Gembloux and Namur . The army was in a bad shape , with many sick . Its leaders , George de Lalaing , Philip de Lalaing , Robert de Melun and Valentin de Pardieu , were absent because they attended the marriage of the Baron of Beersel and Marguerite de Mérode in Brussels . The command of the army was in the hands of Antoine de Goignies , Seigneur de Vendege . < ref name = " Colley Grattan . Holland p . 113 " / > Other notable commanders of the Netherlandish army were the Count of Boussu , Martin Schenck ( who after the defeat at Gembloux , enlisted in the Army of Flanders ) , Emanuel Philibert de Lalaing , Philip , Count of Egmont ( Philip broke off all contact with William of Orange in 1579 , and offered his services to King Philip II of Spain , for whom he reconquered several cities ) , William II de La Marck , Lord of Lumey , and Charles Philippe de Croÿ , Marquis d ’ Havré . < ref name = " " Philip II of Spain " . p . 224 " > " Philip II of Spain " . p . 224 < / ref > When De Goignies learned that the Spanish army was approaching Namur , he decided to withdraw to Gembloux . Parma ' s action . At dawn on 31 July , the Spanish army marched towards the rebel army , with the cavalry under Don Octavio Gonzaga in forefront , followed by musketeer s and infantry commanded by Don Cristóbal de Mondragón , and then , the bulk of the army led by Don John of Austria and Don Alexander Farnese . The rear of the army was left in the hands of the Count of Mansfeld . The Spanish cavalry had crossed the Meuse River and made contact with the rear of the rebel army . With the bulk of his army still south of the Meuse , Don John sent messages to his cavalry , now commanded by Don Alexander , not to approach the enemy to closely until the arrival of rest of the troops . < ref name = " Colley Grattan . Holland p . 113 " / > But Alexander , seeing the sorry state of the enemy forces , and advised by Mondragón and Gonzaga of the opportunity to surprise the enemy , gave the order to charge . The Netherlandish cavalry , which protected the rear of the army , after several confrontations against the Spanish cavalry , fled towards their army , causing an enormous panic amongst the rebel troops . < ref name = " Colley Grattan . Holland p . 113 " / > The result was a crushing victory by Parma ' s cavalry . The entire army was instantaneously disintegrated , and the Spanish cavalry , practically unopposed , carried out a massacre on the fleeing troops . Destruction of the States - General ' s army . The Netherlandish army tried to regroup , but a cannon and its ammunition blew up , causing many deaths and a new panic reaction . Meanwhile , part of the rebel troops , mostly Dutch and Scots , led by Colonel Henry Balfour , tried to take defensive positions , but they could not do anything against the musketeers and pikemen led by Don John , Mondragón and Gonzaga . The Spanish victory was complete , < ref name = " Hernán / Maffi p . 24 " > Hernán / Maffi p . 24 < / ref > De Goignies was taken prisoner , among great part of his officers , < ref name = " Colley Grattan . Holland p . 113 " / > Don John captured 34 flags and banners , with the whole of the artillery and baggage of the enemy , and thousands of rebel soldiers were killed or captured . < ref name = " Colley Grattan . Holland p . 113 " / > On the other hand , the Spanish casualties were minimal , about 12 dead and a few wounded . 3 , 000 men reached Gembloux and closed the gates , but after negotiations , the rebels surrendered to the Spaniards on February 5 , and the city was spared from plunder . The Spanish had been less lenient directly after the battle . Hundreds of prisoners had been killed by hanging or drowning . Aftermath . The defeat at Gembloux forced Prince William of Orange , the leader of the revolt , to leave Brussels , along with its nominal Governor , Matthias of Austria ( the future Holy Roman Emperor ) , who had accepted the position of Governor - General by the States - General , although he was not recognized by his uncle , Philip II of Spain . The victory of Don John also meant the end of the Union of Brussels , and hastened the disintegration of the unity of the rebel provinces . Don John died 9 months after the battle ( probably by typhus ) , on October 1 , 1578 , and was succeeded by Don Alexander Farnese as Governor - General ( last desire of Don John that King Philip II confirmed ) , who at the head of the Spanish army reconquered large parts of the Low Countries in the following years . On January 6 , 1579 , the provinces loyal to the Spanish Monarchy signed the defensive Union of Arras , expressed their loyalty to the King Philip II and recognized Don Alexander Farnese as Governor - General of the Netherlands . In contrast , the provinces loyal to the Protestant cause signed the defensive Union of Utrecht .