Russia, Germany, Iberia, and Italy were quite fractured for much of the Middle Ages and time after.
What small or medium sized states that were eventually absorbed and forgotten could have become nations as powerful and renowned in their times as France, Spain, and the Ottoman Empire, et cetera?
Also, when they become these great empires, is there a chance that they could retain their name, or will they adapt it to represent their new territory, like Castilla did when it united Hispania, Moskva did when it united the Russian lands, and Prussia did when it united the German lands? For example, could we, in modern times, call England "Normandy"? Could we call France "Burgundy"?
I'm mostly talking about Europe here but the states do not need to be in Europe necessarily.