15..: New organ by unknown organbuilder.
1641: Reconstruction by Hinrich Speter
1677: Repairs by Arp Schnitger to bellows and windchests. Changes to the specification.
1727-1729: Repairs by O.D. Richborn.
1734: Repairs by Reinerus Caspary
1752: Repairs by Johann Dietrich Busch.
1784-1786: Johann Paul Geycke moves the organ to the west of the church and constructs a new case
Photo from: http://www.st-severini.de
1889: Repairs by Marcussen
1904: Alterations by Paul Rotherin in the old case of 1786.
1959: Reconstruction by Rudolf von Beckerath, several old ranks are still present.