The city of Edo (modern Tokyo) had grown by the early nineteenth century to a metropolis with a population of more than one million. The center of commerce and government administration under the Tokugawa shoguns, Edo was visited by many travelers and was the required residence in alternate years for the daimyo, the warrior rulers of provincial domains. The artist Hiroshige is primarily known as a designer of commercially published woodblock prints, the popular art of the Edo period (1615-1868).