Empire: Total War is set during the 18th century, said to be the most requested time period by the Total War community. The game will introduce naval combat to the series, which will result not only in ship-to-ship combat, but also boarding of ships and engaging in hand-to-hand combat on the decks.
Empire also promises further refinements to the series' 3D battles and turn based campaign map including improved trade, diplomacy and espionage systems, a refined and streamlined UI, and improved advisors. You can find two screenshots here. nope