It became the of Japan in the middle of , when its name changed from "" to "Tokyo". Before then, was the capital of Japan. The , or , lived in Kyoto. Edo was the place where the lived. The city grew up under the control of the . Before then it was a small town on the sea. Edo means "the mouth of a river" in Japanese.
Tokyo is an extremely interesting place, your challenge is to do some research into the city and create a mind map on it by writing all the interesting facts you find. You can do this on Purple Mash, draw it in your book or create a poster, it's entirely up to you.