They determined to compel Denmark to join England and Sweden, and to hold the fleet at Copenhagen as a gauge of Danish fidelity.
That momentous resolve was formed on or just before July the 16th, in consequence of news that had arrived from Memel and Tilsit.

The exact purport of that news, and the manner of its acquisition, have been one of the puzzles of modern history.

But the following facts seem to furnish a solution.

Our Foreign Office Records show that our agent at Tilsit, Mr.Mackenzie, who was on confidential terms with General Bennigsen, left post haste for England immediately after the first imperial interview; and the news which he brought, together with reports of the threatening moves of the French on Holstein, clinched the determination of our Government to checkmate the Franco-Russian aims by bringing strong pressure to bear on Denmark.

To keep open the mouth of the Baltic was an urgent necessity, otherwise we should lose touch with the Anglo-Swedish forces campaigning against the French near Stralsund.[160] Furthermore, it should be noted that Denmark held the balance in naval affairs.