In 1643, the Thirty Years War raged across continental Europe for the past 25 years. In 1635, Catholic France joined with the Protestant Germans, Dutch and Scandinavians against their political rivals the Catholic Hapsburgs of Austria and Spain. The indomitable Cardinal Richelieu of France had been bankrolling Sweden and the Protestants for years, but after the disastrous Swedish defeat at Nordlingen, entered France into the war directly to prevent Hapsburg hegemony in all of its surrounding lands on the continent. In 1640, Richelieu started war against Spain “by diversion”, funding Catalan, Basque, Portuguese, and Dutch insurgents which he hoped would force Spain to sue for peace. By 1643, the plan was working.

Spain needed to defeat France quickly. Moreover, Cardinal Richelieu died that winter and Louis XIII fell horribly ill. So in the spring, a combined Spanish, German, Italian, and Walloon army marched on France through the Ardennes Forest to avoid the main French armies in Flanders, (I wonder if that would ever happen again…) and capitalize on the political confusion associated with the transfer of power and royal succession in Paris. The Spanish Army of Flanders under Francisco de Melo had invaded France through the Ardennes before and defeated the French at the Battle of Honnecourt in 1642. However, Melo decided not to proceed to Paris due to the training and suspect loyalties of his Walloon cavalry. He vowed not to make the same mistake again.

But this year the French were prepared. Melo stopped and invested the French fortified town of Rocroi to secure his line of communication back to Flanders. The garrison sent frantic messages that they could withstand the siege for but two days. Fortunately, the French army was at Amiens under the young 21 year old Louis II Duc d’Enghien and Prince de Conde, placed just so to stop any future penetration of the Ardennes (…). D’Enghien rushed to Rocroi to break the siege before a reinforcing column of Spanish arrived. During the march, D’Enghien learned via secret courier that the King died that evening, and the throne passed to four year old King Louis XIV and his regent, the Queen-mother Anne of Austria. He wisely kept the news from his men: the death of the king would shatter the morale of his army and a loss at Rocroi would send France into chaos.

On the evening of 18 May, both armies lined up opposite each other outside of Rocroi. That night, Melo infiltrated a thousand arquebusiers under his most trusted subordinate, General Baltasar de Mercader, to ambush the French when they inevitably attacked in the morning. However, D’Enghien might have been young, but he was not inexperienced. The Princes of Condé campaigned for the Bourbons since the day they could keep themselves in the saddle. D’Enghien encouraged deserters and exploited his coreligionist Spain’s use of Catholic Walloons, Germans, and Flemings in invading France, instead of fighting Protestants. The French were neighbors, the distant Spanish were not; one of the first signs of the rise of nation-state codified five years later in the Treaty of Westphalia. Deserters from Spain’s allies were rampant, and Melo’s ambush was discovered and annihilated before dawn. Those troops, and more consequently Mercader, Melo’s best infantry commander, were sorely missed the next day.

At dawn, the battle was joined. D’Enghien attacked with his pikemen, musketeers, and arquebusiers in the center, and with his cavalry on the right. The cavalry on his left he held back due to the marshy terrain. The infantry fight in the center devolved into a stalemate that favored the Spanish tercios. The Spanish tercios were the scourge of Europe for the last 150 years, virtually unbeatable on the battlefield in a head to head melee.

A tercio was a Spanish infantry formation that combined the defensive power of a phalanx of pikes with the offensive power of sword and buckler men and the firepower of protected arquebusiers. But the tercio required professional or highly trained troops to operate effectively, especially on the offense. After 25 years of constant warfare, the Spanish no longer had enough veterans, and had to rely on less disciplined and trained proxies to fill out their formations. This was compounded by technical advances in arquebuses, cannon, and the recent introduction of rifled barrels and early flintlock muskets.

The tercios’ density gave it an unquestionable resilience on the defensive, but that same density limited the amount of troops able to engage the enemy. In contrast, the French, Dutch, and most famously the Swedes, experimented with line and block formations: lines of musketeers supported by blocks of pikemen. The line and block formations were relatively easy to control, and allowed a much greater percentage of the formation to engage, albeit at the expense of depth. The French flexibility and firepower offset the Spanish durability. Unfortunately for the Spanish, the proud commander of the center, Paul-Bernard de Fontaines was bed ridden and had to be carried on a litter. Without an aggressive commander to push them forward, the fight in the center stalemated, something that rarely happened to the tercios. The question became, who would break first?

On the left, the impetuous French cuirassiers attacked without orders through the marsh, became disordered and were smashed by a counter charge of German cavalry. However, the commander of the Spanish right wheeled his men to attack the French center, and exposed his own flank in the process. D’Enghien promptly dispatched his reserve and stabilized his left.

On the right, the French cavalry was under command of Louis XIII’s most experienced, energetic, and finest cavalry tactician, and mentor and kindred spirit to D’Enghien, Jean de Gassion. Gaisson crushed the suspect Walloon horse of the Spanish left. But instead of wheeling to attack the center as the Spanish had, Gaisson and D’Enghien led the superior French cavalry and charged the weak and novice German and Italian tercios of Melo’s reserve. The inexperienced tercios promptly routed and Gaisson seized all of Melo’s cannon. The Spanish center was surrounded.

Melo, rushing hither and yon about the battlefield trying to rally his broken cavalry, had to seek refuge among his tercios lest he be captured by the marauding French cavalry, who had free rein of the battlefield beyond the thrust of a pike around the Spanish center. Melo joined an Italian tercio, where he vowed to “die with the Italian gentlemen.” However, before they broke and he died, he led them away in a fighting retreat, and escaped.

Fontaines and the Spanish center was attacked on all sides by the French and was down to just one Burgundian and four Spanish tercios. Despite the merciless pounding they received from the French musketeers, Fontaines decided to stay and fight. His remaining men were the hard core of the Spanish Army of Flanders and they would die before breaking. Fontaine would fight it out and wait for the reinforcing column. The 6000 fresh troops would break D’Enghien’s weary men and rescue Fontaines. However, the reinforcing column stopped just three miles from the battlefield when it was met by the routed Germans and Walloons who told the commander the day was lost. Instead of confirming the information, the commander withdrew, leaving Fontaines to his fate.

An hour or so later D’Enghien brought forward all of the French and captured Spanish cannon and turned them on the remaining tercios. They pounded the unflinching Spaniards and Bugundians. Fontaines was shot and killed soon thereafter. The senior Spanish colonel offered D’Enghien terms to surrender, but when D’Enghien came forward under a flag of truce to negotiate, he was accidentally fired upon. This enraged the proud French whom massacred the offending tercio to a man. The remaining Spanish and Burgundians quickly surrendered to avoid the same fate.

The Battle of Rocroi signaled the beginning of the end of the Thirty Years War, and the weary belligerents signed the Treaty of Westphalia in 1648. More importantly, the battle heralded French dominance in continental European affairs that ended only with Germany’s rise two century’s later. The Battle of Rocroi was seen as a good omen for the new king, the four year old Louis XIV whose ascendance to the throne was announced simultaneously with the victory by Richelieu’s replacement and protégé, Cardinal Mazarin. Fears of the Queen-mother, Anne of Austria being a Hapsburg puppet were ill founded. She was as dedicated to France as she was to her son, the future “Sun King”. Louis XIV would reign over France’s Golden Age. D’Enghien, soon named the “Grand Conde”, was one of his greatest commanders.