A long time ago, Ukraine was a part of a bigger country called the Soviet Union. But then, the Soviet Union fell apart, and Ukraine wanted to be its own independent country. However, some people in Ukraine didn't agree and wanted to stay with the Soviet Union.
So, there was a big argument and some people started fighting each other. One group was the Ukrainian government, who wanted independence. Another group was called the Russian "separatists," who wanted to stay with Russia.
The fighting got really bad and many people got hurt. The Ukrainian government even had to ask for help from other countries to stop the fighting. But eventually, after a lot of hard work and negotiations, Ukraine was recognized as an independent country and the war ended.
It was a very difficult time for Ukraine, but it was important because they were able to become their own country and make their own decisions.