During the Deluge the Brandenburg army included two different elements. One included units formed in Brandenburg, the other, territorial defense units from Ducal Prussia, where the power was held by the Brandenburg elector. The army of Brandenburg had been undergoing a process of transformation since 1644, the aim was to increase and improve the efficiency of the standing army consisting of mercenary forces. The Prussian territorial defense on the other hand, comprised of infantry made up of peasants, cavalry of the levy of nobility and territorial dragoons, was small in numbers, poorly trained and equipped so it was unable to properly fulfill its functions. In 1655 a speedy modernization process was started in the Ducal Prussian army independent companies were combined into regiments, numbers of some units were supplemented by enlistment and conscription. On several occasions during the Deluge mercenary regiments from Brandenburg were sent to Prussia where they substantially supported the elector’s forces. In 1656 the Brandenburg-Prussian army in Ducal Prussia numbered about 14,000 soldiers and this number increased until the end of the war. The three main formations are infantry, reiters and dragoons; formed into regiments and squadrons of several companies (half-regiments). Apart from mercenary regiments (regular) a large part of the army is made up of Prussian Prussian militia and territorial troops with worse training and equipment. On the battlefield the Brandenburg army can rely on good regular pike and shot infantry and the Prussian musketeers. Cavalry consists of regular reiters and the somewhat weaker Prussian reiters. The army also includes dragoons as well as light and medium artillery. The elector’s forces can also count on their silver-tongued diplomats who often are able to gain more at the negotiation table than muskets and cannon on the field of battle. However, the army must focus on the defense of Ducal Prussia which can influence its tactics. By changing the network of his alliances the elector also influences the army’s composition as today’s ally may be an enemy tomorrow.