There's many battles, adwa is important because it signifies our independence as Italy was forced to sign a treaty where they recognized us as an independent entity. Ethiopia is the only country in Africa to not only maintain independence but also go on to set its own borders. Meaning if Europeans did t colonize Africa most of the countries would not exist as they are today.
Cmon mate, we all know the reason why "Ethiopia is the only country in Africa not to get colonised" is simply for one reason and one reason only: Christianity.
The whole purpose of colonialism was the hunger and greed for resources, second to that was the spreading of Christianity. Since Ethiopia is the oldest Christian country (disputed with Armenia), where some of the earliest Bibles were written, and the land being a mostly mountainous terrain, there was no need to colonize the place.
Then comes crazy Benito Mussolini, thinking he's the next Ceasar and reform the Roman Empire. He then goes against European colonialism rules and attacks you lot, then the other colonial powers arm you to the teeth, with modern weapons (rifles and artillery guns) to protect a people who have been worshipping Jesus for centuries before themselves.
And that is the reason you were never colonised by the likes of Britain and France. And you lot weren't even the only Africans to never be colonised. Liberia to was never colonised, but then again even they were founded and propped up by another western nation ( America) as a free state under its protection.
Now run along, your plate of raw hyena meat is calling for ya.