  Scaling relations for globular clusters (GC) differ from scaling relations
for pressure supported (elliptical) galaxies. We show that two-body relaxation
is the dominant mechanism in shaping the bivariate dependence of density on
mass and Galactocentric distance for Milky Way GCs with masses <10^6 Msun, and
it is possible, but not required, that GCs formed with similar scaling
relations as ultra-compact dwarf galaxies. We use a fast cluster evolution
model to fit a parameterised model for the initial properties of Milky Way GCs
to the observed present-day properties. The best-fit cluster initial mass
function is substantially flatter (power-law index alpha =- 0.6+/-0.2) than
what is observed for young massive clusters (YMCs) forming in the nearby
Universe (alpha =~-2). A slightly steeper CIMF is allowed when considering the
metal-rich GCs separately (alpha =~-1.2+/-0.4$). If stellar mass loss and
two-body relaxation in the Milky Way tidal field are the dominant disruption
mechanisms, then GCs formed differently from YMCs.
