1) Battle of Gaxia-This is the battle where the Han Empire confirmed that the unification of China under the Qin was to be the deciding aspect of civilization in East Asia. With this battle the 2,000 years of subsequent Chinese unity under the Dynasties and the later PRC reunification were settled. This IMHO qualifies it for number 1 on this list as its results remain enshrined 2,000 years later.
2) Tie between the Battles of Yarmouk and Qasidiyya-These were the battles that made the Islamic Empire and with it Muslim civilization happen. The one collapsed the southern wing of the ERE, the other destroyed Sassanian Persia. Due to both we have the Islamic world of the present. Thus why these two are number 2.
3) Battle of Actium-Confirmed that Rome would fall under one-man hereditary monarchy, and that monarch would be from the Julio-Claudian lineage. This of course drastically changed Western Eurasia and is why it qualifies for number 3.
4) Battle of Poltava-Launched Russia into Central Europe. That is all.
5) Tie between Battles of Kosovo and Nicopolis-Redrew the map of the Balkans for a space-filling Empire for the next few centuries, also classic subversions of the European way of war concept.
6) Battle of Leipizig-Broke Napoleon Bonaparte for good. A tie in this regard with Waterloo.
7) Battle of Sedan-The battle that broke France in 1870.
8) Battle of Koniggratz-The battle that made AH and all the evils that went with it.
9) Battle of Valmy-The battle that saved the French Revolution.
10) Battle of Malyaroslavets-The battle that doomed the Grande Armee of 1812.
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If you guys had to pick 10/15 such battles, which would you pick? Does the concept have any actual meaning?