  Merging the Chandra and XMM-Newton deep surveys with the previously
identified ROSAT sample, almost 1000 AGN-1 covering five orders of magnitude in
0.5-2 keV flux limit and six orders of magnitude in survey solid angle were
identified with ~95% completeness. AGN-1 are by far the largest contributors to
the soft X-ray samples. Their evolution is responsible for the break in the
0.5-2 keV source counts. Their soft X-ray luminosity function clearly changes
shape as a function of redshift, confirming earlier reports of
luminosity--dependent density evolution. The space density with redshift
changes significantly for different luminosity classes, showing a strong
positive evolution up to a certain redshift and then a flattening. The
redshift, at which the evolution peaks, changes considerably with X-ray
luminosity. The amount of density evolution also depends strongly on X-ray
luminosity, more than a factor of 100 at high luminosities, but less than a
factor of 10 for low luminosities. For the first time, a significant decline of
the space density of X-ray selected AGN towards high redshift has been
detected. No significant evolution of the X-ray to optical spectral index is
found for AGN-1. The constraints from the AGN luminosity function and evolution
in comparison with the mass function of black holes in local galaxies
indicates, that the average supermassive black hole has built up its mass
through efficient accretion and is likely rapidly spinning.
