  We study, using quantum Monte-Carlo simulations, the bosonic Kondo-Hubbard
model in a two dimensional square lattice. We explore the phase diagram and
analyse the mobility of particles and magnetic properties. At unit filling, the
transition from a paramagnetic Mott insulator to a ferromagnetic superfluid
appears continuous, contrary to what was predicted with mean field. For double
occupation per site, both the Mott insulating and superfluid phases are
ferromagnetic and the transition is still continuous. Multiband tight binding
Hamiltonians can be realized in optical lattice experiments, which offer not
only the possibility of tuning the different energy scales over wide ranges,
but also the option of loading the system with either fermionic or bosonic
atoms.

Quantum Gases