Largely overlooked by modern historians, the scriptural geologists in Britain in the first half of the nineteenth century tenaciously defended Genesis 1–11 as a reliable historical account, including the Noachian Flood as a unique global catastrophe, against the many compromises with old-earth geological theories. This was the era of Smith, Buckland, Sedgwick, Lyell and Cuvier. To understand and appreciate the scriptural geologists, their historical context is discussed, beginning with the intellectual and religious background, and the historical developments in geology, palaeontology and cosmology that shaped the social and religious milieu of the early nineteenth century. Also relevant is the approach to biblical interpretation through the preceding centuries and amongst their contemporaries. Finally, what credentials were needed then to be a geologist are examined, so that the geological competence of these scriptural geologists to expound and defend Genesis geology may be established.