Below is the fastest way to install the latest trunk version (currently 1.9.6) of Battle of Wesnoth on your Ubuntu Natty Narwhal. Note: it will probably install a bit too many packages than you really need.
sudo apt-get install automake debhelper libboost1.42-all-dev libboost1.42-dev libboost-dev libboost-iostreams-dev libboost-regex-dev libboost-serialization-dev libboost-test-dev libdbus-1-dev libfreetype6-dev libfribidi-dev libghc6-pango-dev liblua5.1-0-dev libpango1.0-dev libsdl1.2-dev libsdl-dev libsdl-image1.2-dev libsdl-mixer1.2-dev libsdl-net1.2-dev libsdl-ttf2.0-dev python-support quilt scons subversion && svn co http://svn.gna.org/svn/wesnoth/trunk wesnoth && cd wesnoth && scons
That’s all – keep in mind that this may take a long time to execute… To play the game, you don’t need to install it, simply type:
./wesnoth .