Vertical crustal motion is a prominent process in Canada because of plate tectonic activity and on-going post-glacial rebound. The process is predominant in the eastern (postglacial rebound) and western (plate tectonics) parts of the country; however, the magnitudes range from a few centimetres to a few millimetres. As a consequence, heights measured over time provide information about vertical motion. Since levelling measurements in Canada are being taken for the past 100 years; there is a wealth of deformation information available to constrain vertical motion.; In this research, a part of the Canadian Precise Levelling Network in eastern Canada is analysed, where both postglacial rebound and plate tectonics are active. The aims of this analysis is to find out, if a kinematic vertical datum can be realized, and also, if the levelling dataset can be created as an independent dataset of vertical motion for geophysical studies. The latter objective will extend the knowledge from deformation studies using other geodetic data (Global Positioning System, Very Long Baseline Interferometry, Satellite LASER Ranging, and absolute gravimetry), which provide information only for the past ≈20 years.; The results from the analysis show that the network has some data gaps, which created excess constraints in addition to minimum constraints that needed to be fixed. This was overcome by using a priori information from postglacial rebound models and height values estimated from a static height adjustment by the Geodetic Survey Division, Natural Resources Canada. On further analysis, it was found that the datum realized with the height values as excess constraints fulfilled one of the objectives of this study---defining a kinematic vertical datum. Here, it is called a workable kinematic vertical datum to distinguish it from minimum constraint and overconstraint datums.; The results were interpreted with geological data, earthquake data, and postglacial rebound models, which all revealed that the region of the network is seismically active and also had effects of postglacial rebound. However, the major contributor to the vertical crustal motion in the region was found to be the postglacial rebound phenomenon. In addition, there were a few local anomalous patterns identified that correlated well with the tectonic faults in the network.; From all these analyses and interpretations it was concluded that a workable kinematic vertical datum can be defined for Canada even with the data gaps. Further, with the realisation of a kinematic vertical datum, an independent dataset of vertical crustal motion rates was created from the levelling dataset for geophysical studies.
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