La Salle was not alone in knowing that those who first met the Indians in the spring secured the best furs at the best bargains.  This information was shared by many, including Francois Perrot.  Just above the island of Montreal is another island, which lies between Lake St Louis and the Lake of Two Mountains.  Perrot, appreciating the advantage of a strategic position, had fixed there his own trading-post, and to this day the island bears his name.  Now, with Frontenac as a sleeping partner of La Salle there were all the elements of trouble, for Perrot and Frontenac were rival traders.  Both were wrathful men and each had a selfish interest to fight for, quite apart from any dispute as to the jurisdiction of Quebec over Montreal.

Under such circumstances the one thing lacking was a ground of action.  This Frontenac found in the existing edict against the coureurs de bois-those wild spirits who roamed the woods in the hope of making great profits through the fur trade, from which by law they were excluded, and provoked the special disfavour of the missionary by the scandals of their lives, which gave the Indians a low idea of French morality.  Thus in the eyes of both Church and State the coureur de bois was a mauvais sujet, and the offence of taking to the forest without a licence became punishable by death or the galleys.

Though Frontenac was not the author of this severe measure, duty required him to enforce it.  Perrot was a friend and defender of the coureurs de bois, whom he used as employees in the collection of peltries.  Under his regime Montreal formed their headquarters.  The edict gave them no concern, since they knew that between them and trouble stood their patron and confederate.

Thus Frontenac found an excellent occasion to put Perrot in the wrong and to hit him through his henchmen.  The only difficulty was that Frontenac did not possess adequate means to enforce the law.  Obviously it was undesirable that he should invade Perrot’s bailiwick in person.  He therefore instructed the judge at Montreal to arrest all the coureurs de bois who were there.  A loyal attempt was made to execute this command, with the result that Perrot at once intervened and threatened to imprison the judge if he repeated his effort.

Frontenac’s counterblast was the dispatch of a lieutenant and three soldiers to arrest a retainer of Perrot named Carion, who had shown contempt of court by assisting the accused woodsmen to escape.  Perrot then proclaimed that this constituted an unlawful attack on his rights as governor of Montreal, to defend which he promptly imprisoned Bizard, the lieutenant sent by Frontenac, together with Jacques Le Ber, the leading merchant of the settlement.  Though Perrot released them shortly afterwards, his tone toward Frontenac remained impudent and the issue was squarely joined.