The sample game demonstrates the game of Diplomacy. In this game, Turkey wins by capturing 18 of the 34 Supply Centers (SCs) on the map.
Sample Games of Original Diplomacy
Maybe not the best game example. This next one is from a 2009 tournament where Russia is able to manage a solo win:
Here's another tournament game where some very small powers are instrumental in preventing a solo by France, eventually earning a draw:
This game features three very common alliances, England/France, Russia/Turkey and a Central Powers Alliance.
It also has an End Of Game thread where the participants explain what they were thinking:
the FULL DISCLOSURE game (PDF). An anonymous game played at webdiplomacy.net where all the private press was eventually gathered so interested parties could see what the private press can look like - see all the lies, all the intrigue! An interesting game between skilled players, although the ending isn't very exciting.