The brief campaign in Cleve and Julich was the last great political operation in which the two were likely to act in even apparent harmony.  But the rivalry between the two had already pronounced itself emphatically during the negotiations for the truce.  The Advocate had felt it absolutely necessary for the Republic to suspend the war at the first moment when she could treat with her ancient sovereign on a footing of equality.  Spain, exhausted with the conflict, had at last consented to what she considered the humiliation of treating with her rebellious provinces as with free states over which she claimed no authority.  The peace party, led by Barneveld, had triumphed, notwithstanding the steady opposition of Prince Maurice and his adherents.

Why had Maurice opposed the treaty?  Because his vocation was over, because he was the greatest captain of the age, because his emoluments, his consideration, his dignity before the world, his personal power, were all vastly greater in war than in his opinion they could possibly be in peace.  It was easy for him to persuade himself that what was manifestly for his individual interest was likewise essential to the prosperity of the country.

The diminution in his revenues consequent on the return to peace was made good to him, his brother, and his cousin, by most munificent endowments and pensions.  And it was owing to the strenuous exertions of the Advocate that these large sums were voted.  A hollow friendship was kept up between the two during the first few years of the truce, but resentment and jealousy lay deep in Maurice’s heart.

At about the period of the return of Aerssens from his French embassy, the suppressed fire was ready to flame forth at the first fanning by that artful hand.  It was impossible, so Aerssens thought and whispered, that two heads could remain on one body politic.  There was no room in the Netherlands for both the Advocate and the Prince.  Barneveld was in all civil affairs dictator, chief magistrate, supreme judge; but he occupied this high station by the force of intellect, will, and experience, not through any constitutional provision.  In time of war the Prince was generalissimo, commander-in-chief of all the armies of the Republic.  Yet constitutionally he was not captain-general at all.  He was only stadholder of five out of seven provinces.

Barneveld suspected him of still wishing to make himself sovereign of the country.  Perhaps his suspicions were incorrect.  Yet there was every reason why Maurice should be ambitious of that position.  It would have been in accordance with the openly expressed desire of Henry IV. and other powerful allies of the Netherlands.  His father’s assassination had alone prevented his elevation to the rank of sovereign Count of Holland.  The federal policy of the Provinces had drifted into a republican form after their renunciation of their Spanish sovereign, not because the people,