The history of Edo-jo dates back to the Heian Period when a fortified palace was built by the Edo clan on this site. In 1457 the Uesugi clan had a vassal construct Edo-jo. The castle remained under the control of the Uesugi family until the coming of the Tokugawa.

Before Tokugawa Ieyasu, Edo (Tokyo) was just another town in the Kanto area. Partly due to Ieyasu's revolutionary city planning, the town of Edo developed at lightning speed and quickly became the social and political center of Japan. The castle, Edo-jo, which was the center of Tokugawa's city, was the largest castle in the world at that time.

In 1657 a great fire swept through Tokyo and destroyed many parts of the castle including the donjon. To this day, the donjon has never been rebuilt. For 264 years, 15 generations of Tokugawa ruled Japan from Edo-jo. The Tokugawa gave up control of the castle when they lost the Boshin war in 1868. The majority of Edo-jo was destroyed by the U.S. bombings of Tokyo during WWII.

Today, a large section of Edo-jo is occupied by the Imperial palace where the emperor and his family reside. The public cannot enter this area but they can enter the Higashi-gyoen (east gardens) and the Honmaru where the donjon once stood. A reconstructed palisade marks the location of the former donjon. It is worth a trip to Edo-jo just to see the immense stone walled moats that remain from the original castle. The stones were simply fitted together and not cemented which is why they were able to withstand the Great Kanto Earthquake without crumbling.