  The masses of supermassive black holes (SMBHs, M_BH=10^6-10^11 Msun) in the
centres of galaxies are related to the host stellar spheroid mass and velocity
dispersion. A key question is how these relations originate, and over which
range of black hole masses they hold. It has been speculated that
intermediate-mass black holes (IMBHs, M_BH=10^2-10^5 Msun) could play a
fundamental role in the growth of SMBHs. A handful of IMBHs has recently been
detected in Galactic globular clusters (GCs), but their masses are inconsistent
with the galactic scaling relations of SMBHs. In this Letter, we derive the
initial properties of the GCs using a standard analytical evolutionary model,
of which the free parameters are fixed by independent constraints. We find that
the observed IMBH masses initially followed the galactic SMBH scaling
relations, and subsequently moved off these relations due to the dynamical
evolution of their host GCs. This work is concluded with a brief discussion of
the uncertainties and the implications of our results for the possible
universality of massive black hole growth.
