When we think about takeout lunches in Japan, we must go back a long way. Surely you have seen in museums the beautiful lacquer lunch boxes the nobility used when they went to the countryside on excursions. These picnics were quite elegant occasions with poetry writing and incense ceremonies. But long before that, probably before the 800s, there were special foods for travelers. Those who feel we are quite advanced today because of the development of instant foods should be aware of "hoshi-ii," an early instant rice. It was dried and, like today, reconstituted by adding water.
"Nigiri-meshi" and "omusubi," both words for rice balls, were known in ancient times. The characters that make up these words mean "gathered" or "pressed together." The rice was often wrapped in bamboo leaves, which we know today have antibacterial qualities. Then there was "tonjiki," usually triangular-shaped rice balls that were prepared in advance for expected visitors, a predecessor of today's "obento" lunches that you see laid out on tables at tourist bus stops waiting for the next load of travelers to arrive. Omusubi were supposedly eaten by women who worked professionally for the government. This indicates that there were other careers for women in addition to marriage and service to some nobleman.
These are the roots of today's bento, or pre-prepared foods for takeout. The word means "distribution." It is said to have been used for the first time in this context by Oda Nobinaga (1534-1582), who had single servings of food put in a simple box for distribution to a large group of people. By Edo times, bento were common and there were many styles of boxes. The simplest ones were made of woven twigs from a willow tree. The utilitarian aluminum lunch box, much like what can be found today, was introduced in Meiji times. Now takeout foods are one of Japan's biggest businesses, and often the throw-away containers are made to suggest old-style boxes of lacquer or bamboo.