History of IAG

The International Association of Geodesy (IAG) is a global scientific organization dedicated to advancing geodesy — the science of measuring and understanding Earth’s shape, gravity field, and rotation. Its origins trace back to 1862 with the establishment of the Mitteleuropäische Gradmessung (Central European Arc Measurement), initiated by Johann Jacob Baeyer to foster international collaboration in determining Earth’s dimensions. This organization evolved into the Europäische Gradmessung (European Arc Measurement) in 1867 and later became the Internationale Erdmessung (International Geodetic Association) in 1886. Following World War I, in 1919, the IAG became one of the founding associations of the International Union of Geodesy and Geophysics (IUGG), and it adopted its current name in 1932.