It's not the Higgs boson that "prevents" FTL. It's the very fundamental structure of relativistic spacetime that does not allow causally connected events at space-like distances.
In todays understanding of elementary particles the Higgs field is a scalar field with a non-vanishing vacuum expectation value (VEV). This Higgs mechanism provides the fundamental masses to the quarks and leptons as well as the massive gauge bosons (the ##Z^0##- and ##W^{\pm}## bosons) via their coupling to the Higgs field. The non-vanishing VEV leads to the mass terms for these fields without violating the underlying local gauge symmetry. Such symmetries are vital for the consistency of this kind of quantum field theory. If you break such a symmetry in any way, the entire model becomes useless, i.e., you cannot make any sense out of it. Now in addition to providing the fundamental masses to the elementary constituents of matter, as with any other physical field in a QFT it also corresponds to a particle. The quantum excitations of the Higgs field appear as scalar particles, the famous Higgs boson. It is the final building block of the Standard Model, observed by the ATLAS and CMS collaboration at the Large Hardon Collider at CERN in 2012.
One should, however, be aware that about 98% of the mass of the matter surrounding is is NOT due to the Higgs mechanism but dynamically generated by the strong interaction, but that's another (not yet fully understood) topic.