In 1702, he served under the joint command of Marlborough and the
Earl of Athlone. During the
Siege of Venlo, a dispute arose with
General Obdam. Ouwerkerk had been appointed General of the Cavalry in 1701, while Obdam received the same rank in 1702. As a result, Obdam sought to alternate command with Ouwerkerk, but Ouwerkerk insisted on retaining sole authority. A temporary compromise was reached by assigning Obdam to lead the cavalry at Venlo, while Ouwerkerk commanded the cavalry with the field army. In february of 1703 Athlone died which created another complex dilemma for the Dutch
regenten, as both
Obdam and Ouwerkerk were eligible to succeed Athlone. Both men had long and distinguished military careers behind them and belonged to the most prestigious families in the country. Like all officers of the time, they were highly sensitive about matters of promotion and seniority. It was therefore decided to postpone the appointment to Field Marshal. Since two armies were needed, they could be assigned separate commands to avoid serving under each other. Obdam led the
Siege of Bonn under Marlborough, while Ouwerkerk took command of the army that covered the siege near
Maastricht.
Action at Tongeren and Maastricht However, the English troops assigned to Ouwerkerk's army were slow to arrive. On 9 May, while Marlborough and Obdam were still besieging Bonn, Villeroi and Boufflers advanced on Tongeren with 57 battalions and 103 squadrons. They knew that Ouwerkerk's forces were not yet at full strength due to the delayed English reinforcements and that his Dutch troops were scattered across their cantonments. Their aim was to overrun Tongeren and catch Ouwerkerk's army off guard. However, the two battalions stationed there managed to hold out for an entire day before surrendering, buying Ouwerkerk enough time to withdraw under the protection of Maastricht's guns. By the time the English troops finally arrived, his force had grown to 38 battalions and 71 squadrons. Despite their significant numerical advantage, the French did not immediately press the attack, instead allowing four days to pass without action. This gave the Allies valuable time to strengthen their positions. However, unaware of the full size of the French force, Ouwerkerk had not fortified all locations equally. It wasn't until the night of 13 to 14 May that the French army advanced, but progress was slow due to darkness and heavy rain. By around seven o'clock, both armies were finally positioned for battle. The right flank of the Allied position was anchored on the brook flowing past Lonaken into the Meuse, while the left was shielded by the artillery of Maastricht. In front of the left wing lay the village of Caberg, where a contingent of troops was stationed. Between Caberg and the right flank, the front line was bordered by a partially sunken road, with the remaining defences bolstered by hastily constructed entrenchments. At first, the French seemed poised to attack the right flank, but around four in the afternoon, Villeroi judged an assault to be too risky and ordered a retreat. This decision dealt a significant blow to French morale and undermined confidence in their commanders. For the Allies, who had narrowly avoided a potentially disastrous defeat, this turn of events was tantamount to a victory. Ouwerkerk's leadership was widely celebrated throughout the army.
Promotion and independent command After the capture of Bonn, it was decided to lay siege to
Antwerp. Ouwerkerk joined Marlborough at the main army, whose task was to keep the main French force occupied. Meanwhile, Obdam, together with the renowned but notoriously difficult engineer-general
Menno van Coehoorn, was assigned two smaller divisions with the task of breaking through the French lines and encircling Antwerp. On 27 June, Coehoorn's division succeeded in breaching the lines, but because Marlborough and Ouwerkerk failed to keep Villeroi's army occupied, a Franco-Spanish force surrounded Obdam's detachment. In the ensuing
Battle of Ekeren, Obdam became separated from his troops, fled the battlefield, and sent word that his army had been annihilated. When it later became clear that
General Slangenburg had preserved the force, Obdam fell into disgrace and was never again entrusted with command in the Dutch army. This incident once again highlighted the poor relations between the various generals in the Allied army. Slangenburg and Coehoorn despised each other, while
Count Noyelles also harboured a deep dislike for Slangenburg. Marlborough and Ouwerkerk, according to the
Earl of Albemarle, did not get along at the start of the campaign either. Marlborough and Albemarle both agreed that waging war under these circumstances was impossible. Although the relationship between Marlborough and Ouwerkerk improved significantly, Ouwerkerk remained, according to Albemarle, highly stubborn and refused to take advice from anyone.
Nicolaes Witsen wrote about the generals:
"It resembles the wrath of Babel, in confusion and division of sentiments." Unsurprisingly, the rest of the campaign proved largely unsuccessful. In August. The Duke of Marborough, dissatisfied with the gains made that year, hoped to be allowed to plan an attack on the fortified French lines defending
Brabant. However, his proposal divided the
council of war. The generals of the right wing of the army, supported Marlborough. However, the left wing of Ouwerkerk consisting mainly of Dutch generals, such as
Dopff and Albemarle, was strongly opposed to they plan. The officers of the small army under Slangenburg also opposed the plan. Strong opposition and the fact that some of Marlborough's original supporters, cooled in their zeal ultimately meant that the
Dutch field deputies did not feel able to give Marlborough permission to attack the French lines. Although
Huy,
Limbourg and
Geldern fell into Allied hands, the Allies failed to bring Villeroi to battle and to break through the French lines. For the 1704 campaign, the Dutch regenten finally appointed Ouwerkerk as Field Marshal. However, this decision once again caused friction among the Dutch generals. Slangenburg felt slighted because Ouwerkerk was not only a few months his junior in rank—a significant factor at the time—but also did not really outshine him in leadership skills or military achievements. As a result, Slangenburg refused to serve under Ouwerkerk’s command. Other generals also threatened to leave the army but were eventually persuaded to stay. Only Coehoorn remained dissatisfied and offered his services to the army of Savoy. However, he died in March before his plans could be realised. During the campaign of that year Marlborough marched with a part of the Allied troops to the
Danube to support the
Holy Roman Emperor and which would lead to the
Battle of Blenheim. Ouwerkerk took command of the remaining troops in the Low Countries, but his campaign was constrained by cautious instructions from The Hague. The Dutch government, anticipating that the decisive front of 1704 would be in Germany, was reluctant to commit to major operations in the Netherlands and urged Ouwerkerk to avoid unnecessary risks. Meanwhile, his opponent, the Franco-Spanish commander Bedmar, had been ordered to maintain a defensive stance. As a result, neither side engaged in decisive action. Ouwerkerk made three lacklustre attempts to break through the French lines and oversaw an ineffective bombardment of Namur. The most tangible Allied gain was the capture of Fort Isabella, though this victory held little strategic significance. While he succeeded in keeping French and Spanish forces occupied in the region, his overall lack of success led to mounting frustration within the Dutch army.
1705 In 1705, Ouwerkerk once again held overall command of the troops in the Low Countries. Meanwhile, Marlborough had led a contingent to the Moselle in an attempt to force a breakthrough, but his efforts proved futile. As Villeroi, with a considerably larger army than Ouwerkerk, laid siege to Huy, Marlborough abandoned his campaign on the Moselle and swiftly returned to the Low Countries with his troops and reassumed command. Huy fell after two weeks but was swiftly retaken. The Allies then refocused their efforts on breaching the French defensive lines guarding Brabant. Ouwerkerk commanded the left wing of the Allied army, which launched a diversion on 17 July, enabling Marlborough to
break through the lines at Elixheim. Following the breakthrough, Slangenburg, who had meanwhile rejoined the army, argued that the Allies should advance on Leuven. Securing the city was crucial for sustaining their logistics if they intended to capture Brussels and could potentially force Villeroi into a decisive battle. However, Ouwerkerk and
Quartermaster General Daniël van Dopff opposed the plan, citing the exhaustion of the troops and the difficulty of bridging the Grote Gete. Marlborough did not challenge their judgment. Instead of advancing on Leuven, he opted for a wide flanking manoeuvre west of the French lines with 80,000 troops, aiming to cut Villeroi off from Brussels. This move, however, led to logistical difficulties, resulting in a month of frustrating manoeuvring. On 30 July, an attempt to cross the Dyle ended in failure. On 18 August, it seemed that Marlborough had finally succeeded in forcing Villeroi into battle near the village of Waterloo, at the Yse river. Despite the strength of Villeroi’s positions, Marlborough argued in favour of an attack. Ouwerkerk was the only Dutch general who supported this plan. His subordinates, led by Slangenburg, viewed the French positions as too formidable. Compounding the issue, Marlborough’s attempt at a flanking manoeuvre failed and caused significant delays. As a result, the plan for battle was ultimately abandoned. Once again, the campaign yielded little in the way of concrete gains.The most significant outcome of the affair at Waterloo, on the banks of the Yse River, was Slangenburg’s dismissal from the army. Throughout his military career, he had only ever tolerated the leadership of King
William III, and now that Marlborough demanded his departure, his position had become untenable. Much of the tension within the Allied army during the 1702–1705 period stemmed from differing strategic priorities. Unlike France, the Dutch Republic did not possess two lines of fortresses, meaning that before the Battle of Ramillies—when much of the Spanish Netherlands fell into Anglo-Dutch hands, an Allied defeat in the field could have allowed the French to carry the war directly onto Dutch territory. This strategic vulnerability was a major concern for the Dutch generals and field deputies, whereas it weighed less heavily on Marlborough. England, in the event of a defeat, would suffer troop losses but did not face the threat of invasion. As a result, English commanders and those leading the subsidy troops were generally more willing to take risks than their Dutch counterparts.
Culmination of his career and death In 1706, Ouwerkerk and Marlborough again jointly commanded the Anglo-Dutch army in the Low Countries. Expectations for the campaign were low, as it was widely assumed that Villeroi would remain behind his defensive lines. However, on 19 May, Villeroi unexpectedly moved out of his fortifications to offer battle. Marlborough and Ouwerkerk advanced their forces and engaged the Franco-Spanish army at the
Battle of Ramillies. Ouwerkerk commanded the left wing and directly led the cavalry. The battle was decided on this flank, where the Allied cavalry gained the upper hand. His leadership thus contributed significantly to the victory, which resulted in the rapid conquest of much of the Spanish Netherlands. During the battle, his generosity nearly cost him his life. When a
Bavarian cavalryman surrendered, Ouwerkerk allowed him to keep his sabre. However, as Ouwerkerk turned away, the Bavarian attempted to stab him. An Allied cavalryman noticed just in time and shot the Bavarian, saving the marshal's life. After the Battle of Ramillies, Ouwerkerk successfully commanded the sieges of Ostend and Ath. The 1707 campaign in the Low Countries was uneventful, as the French avoided battle and Marlborough made no effort to force an engagement, preferring to wait for the outcome of the
assault on Toulon. For months, the opposing armies remained idle, facing each other without significant action. One of the few notable events of the campaign was Ouwerkerk’s success in thwarting an attack on
Brussels. On July 4, he learned of a French plan to set fire to the city's forage depot. Acting swiftly, he reinforced the garrison with two battalions—just in time. That same night, 150 French troops approached the city, but they were quickly discovered and fled immediately. The 1708 campaign, by contrast, was one of the most remarkable and prolonged of the era, and Ouwerkerk once again played a significant role. At the
Battle of Oudenarde, he commanded the 25,000 troops on the left wing, whose flanking manoeuvre decisively turned the battle in favour of the Allies. As with Ramillies, Dutch troops captured the most French flags and standards—trophies that were highly prized during this period as symbols of victory.
Sicco van Goslinga, one of the
Dutch field deputies, recorded a remarkable scene that took place after the Battle of Oudenarde. Sensing that his end was near, Ouwerkerk ordered all the captured trophies from Oudenarde to be displayed in a hall: He participated in the
Siege of Lille (1708), but died just days before the city's capitulation on 18 October, having been bedridden for four days. The last order he signed abolished the use of pikes in the Dutch infantry, as they had once again proven ineffective during the
Battle of Wijnendale. As commander of the Dutch forces, he was succeeded by
Count Tilly. His death was a major blow for the Dutch army. Although Ouwerkerk lacked the prestige of Marlborough, he had been the undisputed Dutch military commander and had played a significant role in the victories achieved. In contrast, despite his achievements, Tilly remained completely overshadowed by the Duke of Marlborough and Eugene of Savoy and lacked the stature to assert himself as the leader of the Dutch generals. ==Legacy==