This considers Gibraltar as a special case in the history of Britains developing empire. Captured by an Anglo-Dutch fleet in 1704, assigned to Britain in the 1713 Treaty of Utrecht, the rock was devoid of the resources and potential for agricultural development that might justify the violence entailed in its conquest. This was a problem for an early observer (the poet John Breval, who described the place in Calpe, 1717), but the development of a taste for unimproved and mountainous landscapes, and a more confident sense of British power as civilizing, made it easier for later observers to justify British possession. The great siege of Gibraltar (1779-1783) cemented the rocks status as British: its bare features acquired an iconic status as a symbol of British independence and freedom, a reference point that could be evoked in the context of other imperial conquests.