The former name for Tokyo was…
Before Tokyo was Tokyo, the area was called Edo (Ja: 江戸). The area of Edo was ruled by the family Tokugawa, and Tokugawa Ieyasu ruled the area from 1603 until 1868, when the Meiji restoration was instated. Ieyasu and his sons were the de facto ruler of Japan during this time, the Tokugawa’s was the Shoguns and kept the country at peace during their reign. The capitol was still in Kyoto (Ja: 京都) where the powerless emperor sat. Kyoto was the capital of Japan from 794 to 1868.
In 1868 that changed, until then kept it’s border closed, they were now forced to open them. Japan started its journey from a feudal society to a more modern west-inspired civilisation. At this time, the capital was moved from Kyoto to Edo, the move meant a name change for Edo. From Edo to Tokyo(Ja: 東京) as we know it to be called today.
The short but interesting story of how Edo became Tokyo.
Bonus info you didn’t know you needed
Look and compare the kanji (Chinese characters) for the two cities, Kyoto 京都 and Tokyo 東京. Notice something? They both share a kanji, the kanji 京 stands for capital. In the case for Tokyo, the 東 (to) stands for east, putting them together we get roughly “eastern capital”.