Although specimens of the dinosaur, Megalosaurus had been collected near Oxford since at least the late seventeenth century, scholars misunderstood the significance of the discovery, believing the fossils to be from fish or the bones of war elephants brought to Britain by the Romans. From the 1790s further specimens were uncovered at a quarry near Stonesfield, about 10 miles north of Oxford. Many were seemingly acquired by William Buckland, Professor of Geology at Oxford, for further study. 
Buckland spent many years studying the specimens without success until a visit from the French naturalist, Georges Cuvier in 1818. Cuvier informed him that the bones seemed to be from a hitherto unknown lizard-like creature, around 12 metres in length. Buckland continued to work on the fossils with his friend William Conybeare and in 1822, they prepared an article describing the creature, which Conybeare named Megalosaurus (Greek for 'Big Lizard'). The piece went unpublished, but the same year, the physician James Parkinson publicly declared the name when describing one of the teeth of the creature. With encouragement from Cuvier, Buckland continued his studies, working with his future wife Mary Morland, who drew the fossils in preparation for lithographs.
On 20 February 1824, Buckland officially announced Megalosaurus at a meeting of the Geological Sociey of London and published his descriptions in the society's journal later in the year. This ensured that Megalosaurus was first non-avian genus of dinosaur to be named.