after the thirty years' war, the rule of the bishops of verden ended and rotenburg became part of the secularized duchy of verden under swedish rule. in this period its new rulers built the castle with the remnants of the "schloss" into a modern fortress as an outpost to protect the main fortress at stade. this rebuilding work required the western part of the town to be demolished, making it necessary to move the main area of settlement to the east. even the parish church had to be taken down and moved to the site of the present town church.