Du Lhut’s exploits and character make him the outstanding figure of the war which Duchesneau waged against the coureurs de bois.  The intendant certainly had the letter of the law on his side in seeking to clear the woods of those rovers who at the risk of their own lives and without expense to the government were gaining for France an unequalled knowledge of the interior.  Not only had the king decreed that no one should be permitted to enter the forest without express permission, but an edict of 1676 denied even the governor the right to issue a trading pass at his unrestrained discretion.  Frontenac, who believed that the colony would draw great profit from exploration, softened the effect of this measure by issuing licences to hunt.  It was also within his power to dispatch messengers to the tribes of the Great Lakes.  Duchesneau reported that Frontenac evaded the edict in order to favour his own partners or agents among the coureurs de bois, and that when he went to Montreal on the pretext of negotiating with the Iroquois, his real purpose was to take up merchandise and bring back furs.  These charges Frontenac denied with his usual vigour, but without silencing Duchesneau.  In 1679 the altercation on this point was brought to an issue by the arrest, at the intendant’s instance, of La Toupine, a retainer of Du Lhut.  An accusation of disobeying the edict was no trifle, for the penalty might mean a sentence to the galleys.  After a bitter contest over La Toupine the matter was settled on a basis not unfavourable to Frontenac.  In 1681 a fresh edict declared that all coureurs de bois who came back to the colony should receive the benefit of an amnesty.  At the same time the governor was empowered to grant twenty-five trading licences in each year, the period to be limited to one year.

The splendid services of Du Lhut, covering a period of thirty years, are the best vindication of Frontenac’s policy towards him and his associates.  Had Duchesneau succeeded in his efforts, Du Lhut would have been severely punished, and probably excluded from the West for the remainder of his life.  Thanks to Frontenac’s support, he became the mainstay of French interests from Lake Ontario to the Mississippi.  Setting out as an adventurer with a strong taste f or exploration, he ended as commandant of the most important posts—­Lachine, Cataraqui, and Michilimackinac.  He served the colony nobly in the war against the Iroquois.  He has left reports of his discoveries which disclose marked literary talent.  From the early years of Frontenac’s regime he made himself useful, not only to Frontenac but to each succeeding governor, until, crippled by gout and age, he died, still in harness.  The letter in which the governor Vaudreuil announces Du Lhut’s death (1710) to the Colonial Office at Paris is a useful comment upon the accusations of Duchesneau.  ‘He was,’ says Vaudreuil, ‘a very honest man.’  In these words will be found an indirect commendation of Frontenac, who discovered Du Lhut, supported him through bitter opposition, and placed him where his talents and energy could be used for the good of his country.