The outbreak of war meant the final ruin of the Dutch Republic. Its internal condition at the close of 1780 made it hopelessly unfitted to enter upon a struggle with the overwhelming sea-power of England. Even had William V possessed the qualities of leadership, he would have had to contend against the bitter opposition and enmity of the anti-Orange party among the burgher-regents, of which Van der Capellen was one of the most moving spirits, and which had its chief centre in Amsterdam. But the prince, weak and incompetent, was apparently intent only on evading his responsibilities, and so laid himself open to the charges of neglect and mal-administration that were brought against him by his enemies.

Against an English fleet of more than 300 vessels manned by a force of something like 100,000 seamen, the Dutch had but twenty ships of the line, most of them old and of little value. Large sums of money were now voted for the equipment of a fleet; and the Admiralties were urged to press forward the work with all possible vigour. But progress was necessarily slow. Everything was lacking - material, munitions, equipment, skilled labour - and these could not be supplied in time to prevent Dutch commerce being swept from the seas and the Dutch colonies captured. The Republicans, or Patriots, as they began to name themselves, were at first delighted that the Orange stadholder and his party had been compelled to break with England and to seek the alliance of France; but their joy was but short-lived. Bad tidings followed rapidly one upon another. In the first month of the war 200 merchantmen were captured, of the value of 15,000,000 florins. The fishing fleets dared not put out to sea. In 1780 more than 2000 vessels passed through the Sound, in 1781 only eleven. On February 3 St Eustatius surrendered to Admiral Rodney, when one hundred and thirty merchantmen together with immense stores fell into the hands of the captors. Surinam and Curacoa received warning and were able to put themselves into a state of defence, but the colonies of Demerara, Berbice and Essequibo were taken, also St Martin, Saba and the Dutch establishments on the coast of Guinea. In the East Indies Negapatam and the factories in Bengal passed into English possession; and the Cape, Java and Ceylon would have shared the same fate, but for the timely protection of a French squadron under the command of Suffren, one of the ablest and bravest of French seamen.

The losses were enormous, and loud was the outcry raised in Amsterdam and elsewhere against the prince of being the cause of his country's misfortunes. "Orange," so his enemies said, "is to blame for everything. He possessed the power to do whatsoever he would, and he neglected to use it in providing for the navy and the land's defences." This was to a considerable extent unjust, for William from 1767 onwards had repeatedly urged an increase of the sea and land forces, but his proposals had been thwarted by bitter opposition, especially in Amsterdam itself. The accusations were to this extent correct that he was undoubtedly invested with large executive power which he had not the strength of will to use. It was at this period that Van der Capellen and others started a most violent press campaign not only against the stadholder, but against the hereditary stadholdership and all that the house of Orange-Nassau stood for in the history of the Dutch Republic. Brunswick was attacked with especial virulence. The "Act of Consultation" had become known; and, had the prince been willing to throw responsibility upon the duke for bad advice he might have gained some fleeting popularity by separating himself from the hated "foreigner." But William, weak though he was, would not abandon the man who in his youth had been to him and to his house a wise and staunch protector and friend; and he knew, moreover, that the accusations against Brunswick were really aimed at himself. The duke, however, after appealing to the States-General, and being by them declared free from blame, found the spirit of hostility so strong at Amsterdam and in several of the Provincial Estates that he withdrew first (1782) to Hertogenbosch, of which place he was governor, and finally left the country in 1784.

The war meanwhile, which had been the cause, or rather the pretext, for this outburst of popular feeling against Brunswick, was pursuing its course. In the summer of 1781 Rear-Admiral Zoutman, at the head of a squadron of fifteen war-ships, was ordered to convoy seventy-two merchantmen into the Baltic. He met an English force of twelve vessels, which were larger and better armed than the Dutch, under Vice-Admiral Hyde Parker. A fierce encounter took place at the Doggerbank on August 5, which lasted all day without either side being able to claim the victory. Parker was the first to retreat, but Zoutman had likewise to return to the Texel to repair his disabled ships, and his convoy never reached the Baltic. The Dutch however were greatly elated at the result of the fight, and Zoutman and his captains were feted as heroes.