  The dynamical features of the irregular satellites of the giant planets argue
against an in-situ formation and are strongly suggestive of a capture origin.
Since the last detailed investigations of their dynamics, the total number of
satellites have doubled, increasing from 50 to 109, and almost tripled in the
case of Saturn system. We have performed a new dynamical exploration of Saturn
system to test whether the larger sample of bodies could improve our
understanding of which dynamical features are primordial and which are the
outcome of the secular evolution of the system. We have performed detailed
N--Body simulations using the best orbital data available and analysed the
frequencies of motion to search for resonances and other possible perturbing
effects. We took advantage of the Hierarchical Jacobian Symplectic algorithm to
include in the dynamical model of the system also the gravitational effects of
the two outermost massive satellites, Titan and Iapetus. Our results suggest
that Saturn's irregular satellites have been significantly altered and shaped
by the gravitational perturbations of Jupiter, Titan, Iapetus and the Sun and
by the collisional sweeping effect of Phoebe. In particular, the effects on the
dynamical evolution of the system of the two massive satellites appear to be
non-negligible. Jupiter perturbs the satellites through its direct
gravitational pull and, indirectly, via the effects of the Great Inequality,
i.e. its almost resonance with Saturn. Finally, by using the Hierarchical
Clustering Method we found hints to the existence of collisional families and
compared them with the available observational data.
