The measures he took and the arbitrary way in which he tried to enforce them, soon brought him face to face with the stubborn resistance of the Estates of Holland under the leadership of Oldenbarneveldt.

In April, 1586, he issued a very stringent placard forbidding all traffic with the enemy's lands and more especially the supplying of the enemy with grain.
He meant it well, for he had been informed that the cutting-off of this commerce, which he regarded as illicit, would deprive the Spaniards of the necessaries of life, and Parma's position would become desperate.
This carrying trade had, however, for long been a source of much profit to the merchants and shipowners of Holland and Zeeland; indeed it supplied no small part of the resources by which those two provinces had equipped the fleets and troops by which they had defended themselves against the efforts of the Spanish king.

Two years before this the States-General had tried to place an embargo on the traffic in grain, but the powerful town-council of Amsterdam had refused obedience and the Estates of Holland supported them in their action.

The deputies of the inland provinces, which had suffered most from the Spanish armies, were jealous of the prosperity of the maritime States, and regarded this trade with the Spaniard as being carried on to their injury.

But Holland and Zeeland supplied the funds without which resistance would long since have been impossible, and they claimed moreover, as sovereign provinces, the right to regulate their trade affairs.