This thread is for things that known widely by common people, but in fact it was WRONG...
(I have use the search function, but thread like this only exist in "non-political chat" forum, so...)
-Decentralisation of Europe was mainly caused by fall of Rome to barbarian hordes.
But in fact, the feudalism has begun as early as the Crisis of Third Century.
-Genghis Khan accomplished all of Mongol conquests in his lifetime.
However, the fact is that Genghis Khan only conquered Central Asia and Northern China (Jin dynasty). The other conquests were accomplished by his successors and generals.
-Spanish conquests of Aztecs and Incas were succeed because of Spain's superior weaponry (guns and cannons).
Actually, it was internal civil wars and diseases that greatly helped the Spanish. The majority of Spanish conquistadors were still using swords and spears at that time, and even there was a lot of natives in Spanish army.
-The failure of ARW would butterflied away British empire at Africa and India, because the British would focused their attention to North America.
But the fact is that even at the time of ARW, the British have firmly established themselves in India. And Africa would still be scrambled by European powers, sooner or later.