The Shogun's Daughter by Robert Ames Bennet

The day after Yuki's discovery, word at last came from Kyoto, sanctioning the Prince of Owari's adoption of his kinsman as son and heir. After that, little time was required to comply with law and custom. The opposition of the Mito faction was paralyzed by the sanction of the Mikado. It was a striking instance of the paradoxical nature of the government of this strange land.

In theory, the Mikado was the sacred and absolute Emperor, and the Shogun only the first among his secondary class of nobles. In fact, he was little more than a figurehead in the hands of the Shogunate, and his sanction of government measures was usually given as a matter of course. A strong Shogun, such as Iyeyoshi, could even enforce compliance against the wishes of so powerful an opposition as the Mito party backed by the reluctance of the _kuge_, or Kyoto nobles. Yet without the Mikado's sanction, however obtained, the Shogun would have become a rebel, with no other means than sheer military force to hold in subjection the great non-Tokugawa _daimios_.