Napoleon, now Emperor of the French, assembled armies on the coast of France to invade Great Britain, but Austria and Russia, Britain's allies, were preparing to invade France. The French armies were christened "La Grande Armée" and secretly left the coast to march against Austria and Russia before those armies could combine. The "Grande Armée" defeated Austria at Ulm the day before the Battle of Trafalgar, and Napoleon's victory at the Battle of Austerlitz effectively destroyed the Third Coalition. In 1806, Britain retook the Cape Colony from the Batavian Republic. Napoleon abolished the republic later that year in favour of the Kingdom of Holland, ruled by his brother Louis. However, in 1810, the Netherlands officially became a part of France.