  Clusters that form in total 10^3 < N < 10^5 stars (type II clusters) lose
their gas within a dynamical time as a result of the photo-ionising flux from O
stars. Sparser (type I) clusters get rid of their residual gas on a timescale
longer or comparable to the nominal crossing time and thus evolve approximately
adiabatically. This is also true for massive embedded clusters (type III) for
which the velocity dispersion is larger than the sound speed of the ionised
gas. On expelling their residual gas, type I and III clusters are therefore
expected to lose a smaller fraction of their stellar component than type II
clusters. We outline the effect this has on the transformation of the mass
function of embedded clusters (ECMF), which is directly related to the mass
function of star-cluster-forming molecular cloud cores, to the ``initial'' MF
of bound gas-free star clusters (ICMF). The resulting ICMF has, for a
featureless power-law ECMF, a turnover near 10^{4.5} Msun and a peak near 10^3
Msun. The peak lies around the initial masses of the Hyades, Praesepe and
Pleiades clusters. We also find that the entire Galactic population II stellar
spheroid can be generated if star formation proceeded via embedded clusters
distributed like a power-law MF with exponent 0.9 < beta < 2.6.
