In 1598, Hideyoshi Toyotomi died. Ieyasu defeated a coalition of Toyotomi loyalist clans in 1600. Then he officially declared Edo was as his base of headquarters. He was appointed to Shogun by the Imperial Court. Ieyasu then established the Edo Shogunate in 1603.
The renovation of the Edo Castle and Edo's infrastructure was started in 1605. The renovation was conducted by local feudal lords as a duty like military service to the government. The renovation lasted for about 70 years.
Edo was the first Japanese area where people intentionally founded a big city in coastal alluvial lowland and carefully reclaimed land from the sea. They established a core water transportation system and a chief port of the economy.
photo: Decoration of the Yomeimon gate at Nikko Toshogu-Shrine. This shrine enshrines Ieyasu as a deity of Tosho Daigongen
I took this photo many years ago.