Here Count Mansfeld, with his mercenary army of free-lances, aided by Christian of Brunswick and others on the side of Friedrich and the Protestants, defeated Tilly in 1622.

But later on Tilly and the Imperialists by a series of victories conquered the Palatinate, which was bestowed upon Maximilian of Bavaria.

Mansfeld, notwithstanding that he had some successes later in the year 1622, could not effectually redeem the situation, Brunswick's army being entirely routed by Tilly in the following year at the battle of Stadtlohn, which virtually ended this particular campaign.
The third period of the war, from 1624 to 1629, is characterized by the intervention of the Powers outside the immediate sphere of German or Imperial interests.

France, under Richelieu, became concerned at the growing power of the Hapsburgs, while James I of England began to show anxiety at his son-in-law's adverse fortunes, though without achieving any successful intervention.

The chief feature of this campaign was the entry into the field of Christian IV of Denmark with a powerful army to join Mansfeld and Christian of Brunswick in invading the Imperial and Austrian territories.