in the summer of 1623 by marching into the Lower Saxon Circle.

With no support forthcoming from other Protestant princes, or even from Christian's recent ally Ernst von Mansfeld, Christian now found himself in a precarious military position with little possibility of reinforcement. To add to this, Tilly had received word of Christian's movements and was now moving to confront him.The second half of July 1623 thus became a period of retreat for Christian's