In 1493, Margaret of Burgundy
began to offer support to Perkin Warbeck
, a pretender to the crown of Henry VII
. She allowed him to remain at her court, and gave him 2,000 mercenaries to aid his battle against the English King.
The Low Countries were a major recipient of English cloth, especially Antwerp. English cloth was in high demand all over Europe, but this was a particularly valuable market for the English - and the cloth trade was also very important to Burgundy. It was not lightly therefore that Henry VII issued an embargo against trade with the Netherlands, ordering exporters to move to Calais. The ruler of the Netherlands responded with a counter-embargo on English trade.
As Margaret of Burgundy's influence faded (she was threatened with the removal of her dowager lands if she did not stop supporting English rebels) and it was realised that this embargo was helping nobody, the Magnus Intercursus was signed. Phillip of Burgundy was also keen to secure English help against France, and so the treaty had very favourable conditions for English merchants. They would be allow to sell their wares anywhere in the Duke of Burgundy's dominion save Flanders, and would not have to pay any tolls or customs.
Another promise of the treaty was that English merchants would receieve impartial justice in the local courts - however, this was not put into practice effectively enough. Phillip also attempted to impose an import duty on English traders, and to confine them to Antwerp.
In 1506, a bizzare shipwreck left Phillip stranded on English soil. Henry VII lost no time in putting on a fabulous party for him, and persuading him to sign a new agreement, nicknamed the Malus Intercursus. This treaty was incredibly one-sided, and was never in fact a realistic basis for fair trade (for instance, it said that English merchants should never have to pay duties or be restricted as to where they can sell their cloth, while Philip's merchants enjoyed no such luxuries).
However, just a year later, Phillip died, and the Magnus Intercursus was re-adopted as the basis on which trade was practiced between the two countries.