 In 1790 the Dawes Point Battery was meant to be the first line of defence against an attack by the Spanish Empire, Napoleon’s French troops in 1810, and the Russian Pacific Fleet in the 1850s (during the Crimean War).This was part of a line of defences that were concentrated on protecting the inner Harbour, these also appear to have been given a low priority.Construction of Fort Denison began in 1841, though the fort was not completed until 1857.