Sharing Data with Russia: Friedrich Wilhelm Bessel and the Geopolitics of Prussian Territorial Data

After Napoleon's defeat in 1815, Polish territory was redistributed once again between Prussia, Russia, and Congress Poland (which came under Tsarist rule). The exact determination of the border between Prussia and Russia was necessary for Russia to secure its foothold in eastern Europe. In 1829 Carl Friedrich von Tenner, Russian General Major and Chief of Topographical and Trigonometric Surveying, asked the Prussian government for permission to continue his triangulations of the Russian border through the Prussian cities of Memel and Königsberg [after 1945: Kaliningrad in the Russian Federation], where he proposed that a new Prussian-supported triangulation by Königsberg University's astronomer Friedrich Wilhelm Bessel link to his. At the time, Prussia's cartographic efforts were incomplete, imprecise, and even embarrassing. Bessel had for some time wanted to conduct triangulations, not for geopolitical reasons, but to determine the shape of the earth, a leading scientific problem of the nineteenth century. Positioned between a defeated France on the west and an expanded Russian Empire on the east, Prussia was reluctant to take anything but a conciliatory stance toward Russia. This presentation examines the geopolitical and scientific consequences of Prussia's willingness to share sensitive territorial data: data that immediately aided the Russian Navy in its hydrographical survey of the Baltic, that firmly established Russia's border with Prussia, and that unexpectedly elevated Prussia's status as a scientific power in the region.