Who first proposed the theory of continental drift?

Alfred Wegener first proposed the modern theory of continental drift.

Wegener presented the idea publicly in 1912 and developed it in his 1915 book The Origin of Continents and Oceans. He argued that the continents had once formed a supercontinent, which he called Pangaea, and had later moved apart.

His evidence included the matching shapes of continental margins, identical fossils found on continents now separated by oceans, and similarities between rock layers and mountain belts. The idea was initially rejected by many geologists because Wegener could not provide a convincing mechanism capable of moving continents.

The later discovery of seafloor spreading, magnetic stripes on oceanic crust, and global patterns of earthquakes and volcanoes supplied the mechanism and evidence for plate tectonics. Continental drift is now understood as part of the broader theory of moving lithospheric plates.