Actually constructed for Brazil by Britain, this ship was an attempt to create the world's most powerful battleship. Official vascillation delayed Brazilian acquisition until the now-named HMS Agincourt finished participating in WW I for the British. The design suffered from overcrowding of the turrets, magazines, and boilers, and the hull strength was weakened by the seven deep holes of the turret wells. Nonetheless, her firepower was impressive.

In "Grand Fleet" Britain was eager to sell battleships to friendly countries to free up tonnage after the Washington Treaty limitations. She sold the ship to the Brazilians as Rio de Janeiro, and in her only war engagement encountered the the Vichy French battleship Lille making a run for home from her West African port. After a long battle, with 30 large-caliber guns between them, Lille was sunk by the Brazilian Navy's finest battleship.