William at once saw the use that might be made of Matthew as a figure-head to rally those who still reverenced the house of Hapsburg and who saw in monarchy the only guarantee of order at home and consideration abroad.

Promptly arresting the Duke of Aerschot, a powerful noble who tried to use Matthew's name to create a separate faction, Orange induced the States General first to decree Don John an enemy of the country [Sidenote: December 7, 1577] and then to offer the governorship of the Netherlands to the archduke, at the same time begging him, on account of his youth, to leave the administration in the hands of William.

After Matthew's entry into Brussels [Sidenote: January 18, 1578] the States General swore allegiance to this puppet in the hands of their greatest statesman.
Almost immediately the war broke out again.

Both sides had been busy raising troops.

At Gembloux Don John with 20,000 men defeated about the same number of Patriot troops.