The royal forces, on the morning of September 23, entered the city at three gates and advanced as far as the Park.  But beyond that point they were unable to proceed, so desperate was the resistance, and such the hail of bullets that met them from barricades and from the windows and roofs of the houses.  For three days almost without cessation the fierce contest went on, the troops losing ground rather than gaining it.  On the evening of the 26th the prince gave orders to retreat, his troops having suffered severely.

The effect of this withdrawal was to convert a street insurrection into a national revolt.  The moderates now united with the liberals, and a Provisional Government was formed, having amongst its members Rogier, Van de Weyer, Gendebien, Emmanuel D’Hoogvoort, Felix de Merode and Louis de Potter, who a few days later returned triumphantly from banishment.  The Provisional Government issued a series of decrees declaring Belgium independent, releasing the Belgian soldiers from their allegiance, and calling upon them to abandon the Dutch standard.  They were obeyed.  The revolt, which had been confined mainly to the Walloon districts, now spread rapidly over Flanders.  Garrison after garrison surrendered; and the remnants of the disorganised Dutch forces retired upon Antwerp (October 2).  Two days later the Provisional Government summoned a National Congress to be elected by all Belgian citizens of 25 years of age.  The news of these events caused great perturbation at the Hague.  The Prince of Orange, who had throughout advocated conciliation, was now permitted by his father to go to Antwerp (October 4) and endeavour to place himself at the head of the Belgian movement on the basis of a grant of administrative separation, but without severance of the dynastic bond with Holland.

King William meanwhile had already (October 2) appealed to the Great Powers, signatories of the Articles of London in 1814, to intervene and to restore order in the Belgic provinces.  The difficulties of the prince at Antwerp were very great, for he was hampered throughout by his father’s unwillingness to grant him full liberty of action.  He issued a proclamation, but it was coldly received; and his attempts to negotiate with the Provisional Government at Brussels met with no success.  Things had now gone too far, and any proposal to make Belgium connected with Holland by any ties, dynastic or otherwise, was unacceptable.  The well-meaning prince returned disappointed to the Hague on October 24.  A most unfortunate occurrence now took place.  As General Chasse, the Dutch commander at Antwerp, was withdrawing his troops from the town to the citadel, attacks were made upon them by the mob, and some lives were lost.  Chasse in reprisal (October 27) ordered the town to be bombarded from the citadel and the gunboats upon the river.  This impolitic act increased throughout Belgium the feeling of hatred against the Dutch, and made the demand for absolute independence deeper and stronger.