A better way to phrase the question if you REALLY wanted to know would be "What nationality was Ghengis Khan".
I knew that Ghengis Khan was a mongolian, but are you really going to believe me now? You've already given the answer away.
You should delete this question and ask again if you are really curious.

Genghis khan isn't anything but dead.

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He's Mongolian. He was leader of a nomadic tribe that rode horses

No, he was not Chinese. He was a Mongol. Yes, he was a 'yellow man', but so what? Both Romans and Vikings were 'white men', that doesn't mean Vikings were Romans.

Genghis Khan was a Mongol. His grandson, I think, some descendant, Kublai Khan was a Chinese Emperor, but of Mongolian ancestry, and he was the one the Italian explorer Marco Polo met with.

I don't know about Europeans, but in America we learned Genghis Khan was a Mongol. Considering American school systems are constantly being put down, I would hope Europeans know that.

I have no idea what language he spoke, or how many he spoke, nomadic people can often speak many languages and dialects if they deal with different ethnic or national groups.

I don't remember if I knew where he was born, but since the Mongolians were nomadic, if I am correct, it might be hard to pin down.

The Genghis Khan (it was an assumed title rather than a name) is well-known to most people of European descent as a Mongol, not to be confused with the Chinese.

His descendants, of course, conquered most of China, and his descendant Kubla Khan was ruling it when the first major reports of China were brought to Europe by the trader Marco Polo. So we do connect the descendants of Genghis Khan closely with China. He himself is best known for his conquests westward, into eastern Europe.

You are getting your history lines and national histories mixed up.

Genghis was born into a sub-tribe of small Mongol tribe, and all the Mongol tribes continuously warred against each other in shifting patterns of alliances of the various tribes. Genghis's first great victory, after a series of battles, was to unify all the various Mongol tribes for the first time ever. Shortly the Uighers voluntarily submitted to Mongol power.

There was no Mongolia before Genghis imposed a coalition on the Mongol tribes. There was no subdivision of Mongolia into Inner and Outer (Chinese controlled and Russian controlled) divisions. He never fought the Han, but did fight and defeat another nearby, independent kingdom (Xi-Xia, which payed tribute to the Han,) –all of which occurs in what is now northwest China/Central Asia. While planning to invade the Jin, events in Central Asia drew him west and continued to draw him further west. He was never a Chinese official, never subservient to any Han ruler, but his grandson Kublai Khan became a great emperor of China.

Genghis Khan is the greatest of the Mongols, and among the most powerful ruler of the most reaching empire in all history.