To that end, on 24 April 1672 in Stockholm, France concluded a secret treaty with Sweden that bound the Scandinavian power to contribute 16,000 troops against any German state that gave military support to the Republic of Holland.

Wrangel, however, failed to answer and refused another attempt at dialogue by the Prince of Anhalt[2] In mid-November the governor, John George II, had received assurance of an impending Swedish invasion, but in Berlin the exact causes and motives for such imminent aggression remained unclear.

The so-called Landvolkaufgebot ("people's call up") went back to medieval legal standards in the state of Brandenburg, by which farmers and citizens could be used in case of need for local defence.

[8] It was also successfully employed in the Altmark to mobilize farmers and heathland rangers (mounted forestry personnel familiar with the terrain) and for defence.

[9] Figures relating the initial strength of this army, almost half of which was to consist of Germans by spring, vary in the sources between 13,000[10] and 13,700 men and 15 guns.

However, this unclear assignment prevented, inter alia, clear orders being issued, so that directions for the movement of the army were only put into effect very slowly.

The Mittelmark, by contrast, could be held with relatively few troops, because to the north there were only a few easily defended passes, near Oranienburg, Kremmen, Fehrbellin and Friesack, through the marshlands of the Havelland Luch and the Rhinluch.

In this way, as a result of the prevailing circumstances, Brandenburg's defences were formed along the line from Köpenick, via Berlin, Spandau, Oranienburg, Kremmen, Fehrbellin and Havelberg to the River Elbe.

In Berlin the garrison was increased to 5,000 men, including the Leibdragoner ("dragoon bodyguard") dispatched by the Elector from Franconia and the reinforcements sent from the province of Westphalia at the end of January.

This inaction was partially due to the internal political conflict between the old and the new government of Sweden, which prevented clear military aims being set.

At the end of January 1675, Carl Gustav Wrangel assembled his forces near Prenzlau and, on 4 February, crossed the Oder with his main body heading for Pomerania and Neumark.

This change in Swedish occupation policy followed swiftly, with the result that repression of the state and the civilian population increased sharply.

The Statthalter of the March of Brandenburg, John George II of Anhalt-Dessau, described this state of limbo in a letter to the Elector on 24 March/3 April 1675 as "neither peace nor war".

[18] The Swedish army entered the Uckermark, passing through Stettin; although the capability of it was not comparable to that of earlier times, the former view of Sweden's military might remained.

The first fighting took place in the region of Löcknitz where, on 5/15 May 1675, the fortified castle held by a 180-man garrison under Colonel Götz was surrendered after a day's shelling to the Swedish Army under the command of Oberwachtmeister Jobst Sigismund, in return for free passage to Oderburg.

The governor (Statthalter) sent troops from Berlin and six cannon as reinforcements under the command of Major General von Sommerfeld in order to be able to mount a coordinated defence of the passes at Oranienburg, Kremmen and Fehrbellin.

Sick and borne on a sedan chair, Field Marshal Carl Gustav Wrangel finally reached Neuruppin on 9/19 June.

At the same time he gave orders to his stepbrother, Lieutenant General Wolmar Wrangel, to bring up the main army and advance with him over the bridge at Rathenow towards Havelberg.

In the meantime, Elector of Brandenburg Frederick William tried to secure allies, knowing full well that the national forces at his disposal were, on their own, not sufficient for a campaign against the military might of Sweden.

As a result of inadequate reconnaissance the arrival of Brandenburg appeared not to have been noticed by the Swedes, and so Frederick William adopted security measures to protect this tactical advantage.

After holding a military council, the Elector decided to break through the line of the Havel that the Swedes had now reached at their weakest point, at Rathenow.

Under the personal guidance of Brandenburg's Field Marshal Georg von Derfflinger, they succeeded in defeating the Swedish garrison consisting of six companies of dragoons in bloody street fighting.

That same day the Swedish main army marched from Brandenburg an der Havel to Havelberg, where the crossing of the Elbe was to take place.

So in order to unite his troops with the main army Field Marshal Carl Gustav Wrangel left for Neustadt on 16/26 June.

Lieutenant General Wolmar Wrangel now retired rapidly north to secure his lines of communication and, as ordered, to unite with the now separated Swedish advance guard.

The first division under Lieutenant Colonel Hennig was dispatched to Fehrbellin, the second under Adjutant General Kunowski was sent to Kremmen, the third under the command of Captain (Rittmeister) Zabelitz was deployed to Oranienburg.

They had the task, with the help of expert local hunters, of getting to the exits to the Havelland Luch swamps ahead of the Swedes, using little known routes through rough terrain.

Since no order was issued to hold the pass at all costs because of its importance for the possible withdrawal of Swedish troops, the Brandenburg division attempted to rejoin the main army.

By the end of July, it counted 7,746 men; it is unknown if this includes fresh recruits, stragglers returning, or the recovery of wounded and sick, or all three.

In the years that followed, Sweden, now forced onto the back foot, had to concentrate on defending its territories in northern Europe against numerous attacks, succeeding in the end only in holding onto Scania.