The ancient Greeks thought the flower bud resembled a dolphin, hence the name Delphinium. In Tudor England, the common name 'larkspur' referred to the flower's supposed similarity to a lark's claw.
Modern delphiniums are hybrids. Breeders crossed species such as D. elatum from the Swiss Alps, D. cheilanthum, a dark-blue Siberian species, and the purple, hooded D. brunonianum from the Himalayas. The commonly grown modern Delphinium elatum type has evolved from these crosses, with the large forms we recognise today having been developed in the early 20th century.