  A novel mechanism to build up a supermassive black hole (SMBH) is proposed.
Here, relativistic radiation-hydrodynamic processes are considered from a
galactic scale to a horizon scale. In the present scenario, the mass of a SMBH
is predicted to be in proportion to the bulge mass, and it turns out that the
SMBH-to-bulge mass ratio is basically determined by the nuclear energy
conversion efficiency from hydrogen to helium, $\epsilon=0.007$. The BH
hierarchy is also addressed in relation to the BH formation in globular
clusters. Futhermore, a new picture for QSO formation is proposed based on the
present SMBH formation scenario. It is predicted that a host
luminosity-dominant ``proto-QSO phase'' exists before the QSO phase, and the
proto-QSO phase is preceded by an optically-thick ultraluminous infrared galaxy
(ULIRG) phase.
