The first that comes to mind is the Ottoman empire.  World power in the 1600-1700s, but it failed to develop the institutions mentioned in this article and fell to Austria-Hungary, Italy, and Britain over the latter half of the 1800s.<p>Lithuania.  Largest country in Europe in the 14th century.  Lost large sections of its territory to Sweden and Russia in the late 1600s and 1700s.<p>All of the Native American nations that were swept aside by the United States.  Much of that was because of disease, but a lot was also because the U.S. was better organized and could pick off individual tribes one-by-one.<p>Mongolia.  Genghis Khan's empire, once one of the largest on earth.  Great fighters, poor administrators.  Eventually overshadowed by China.