Short answers, pulled from the story.
Tokyo officially became the imperial capital on the 3rd of September, 1868, when the city was renamed from Edo to Tokyo, meaning Eastern Capital, and Emperor Meiji moved the imperial seat from Kyoto. The former Edo Castle became the new Imperial Palace.
The Great Kanto Earthquake struck on the 1st of September, 1923, with an estimated magnitude of 7.9. The earthquake and subsequent fires killed an estimated 105,000 people in Tokyo and caused economic losses amounting to 37 percent of Japan's total output. The disaster accelerated the shift from brick to concrete construction across the city.
Large-scale Allied bombing of Tokyo began in late 1944. The deadliest single night was Operation Meetinghouse on the 9th-the 10th of March, 1945, when nearly 700,000 incendiary bombs were dropped on the Shitamachi district. The campaign is estimated to have killed between 75,000 and 200,000 civilians and destroyed more than half the city. Tokyo's population fell from 6,700,000 in 1940 to fewer than 2,800,000 by 1945.
As of 2023, the city proper had over 14 million residents. The Greater Tokyo Area, which includes Tokyo and parts of six neighboring prefectures, had 33 million residents, making it the third-most populous metropolitan area in the world.
The Metropolitan Area Outer Underground Discharge Channel is the world's largest underground floodwater diversion facility. It is a 6.3 km tunnel system located 22 metres underground with cylindrical tanks each large enough to fit a Space Shuttle or the Statue of Liberty. It took 13 years to build and was completed in 2006, diverting excess river water to the Edo River during floods.
Tokyo hosted the Summer Olympics in 1964, becoming the first city in Asia to hold the Games. It hosted a second time in 2021, after the originally scheduled 2020 Games were postponed due to the COVID-19 pandemic, making Tokyo the first Asian city to host the Olympics twice.