Europasaurus is a basal macronarian sauropod, a form of quadrupedal herbivorous dinosaur. It lived during the Late Jurassic (middle Kimmeridgian, about 154 million years ago) of northern Germany, and has been identified as an example of insular dwarfism resulting from the isolation of a sauropod population on an island within the Lower Saxony basin.
In 1998, a single sauropod tooth was discovered by private fossil collector Holger Lüdtke in an active quarry at Langenberg Mountain, between the communities of Oker, Harlingerode and Göttingerode in Germany. The Langenberg chalk quarry had been active for more than a century; rocks are quarried using blasting and are mostly processed into fertilisers. The quarry exposes a nearly continuous, thick succession of carbonate rocks belonging to the Süntel Formation, that ranges in age from the early Oxfordian to late Kimmeridgian stages and have been deposited in a shallow sea with a water depth of less than . The layers exposed in the quarry are oriented nearly vertically and slightly overturned, which is a result of the ascent of the adjacent Harz mountains during the Lower Cretaceous. Widely known as a classical exposure among geologists, the quarry had been extensively studied, and visited by students of geology for decades. Although rich in fossils of marine invertebrates, fossils of land-living animals had been rare. The sauropod tooth was the first specimen of a sauropod dinosaur from the Jurassic of northern Germany.
After more fossil material was found, including bones, excavation of the bone-bearing layer commenced in April 1999, conducted by a local association of private fossil collectors. Although the quarry operator was cooperative, excavation was complicated by the near-vertical orientation of the layers that limited access, as well as by the ongoing quarrying. The sauropod material could not be excavated directly from the layer but had to be collected from lose blocks that resulting from blasting. The exact origin of the bone material was therefore unclear, but could later be traced to a single bed (bed 83).