  We present spectral classifications for 438 B-type stars observed as part of
the VLT-FLAMES Tarantula Survey (VFTS) in the 30 Doradus region of the Large
Magellanic Cloud. Radial velocities are provided for 307 apparently single
stars, and for 99 targets with radial-velocity variations which are consistent
with them being spectroscopic binaries. We investigate the spatial distribution
of the radial velocities across the 30 Dor region, and use the results to
identify candidate runaway stars. Excluding potential runaways and members of
two older clusters in the survey region (SL 639 and Hodge 301), we determine a
systemic velocity for 30 Dor of 271.6 +/- 12.2 km/s from 273 presumed single
stars. Employing a 3-sigma criterion we identify nine candidate runaway stars
(2.9% of the single stars with radial-velocity estimates). The projected
rotational velocities of the candidate runaways appear to be significantly
different to those of the full B-type sample, with a strong preference for
either large (>345 km/s) or small (<65 km/s) rotational velocities. Of the
candidate runaways, VFTS 358 (classified B0.5: V) has the largest differential
radial velocity (-106.9 +/- 16.2 km/s), and a preliminary atmospheric analysis
finds a significantly enriched nitrogen abundance of 12+log(N/H) > ~8.5.
Combined with a large rotational velocity (vsini = 345 +/- 22 km/s), this is
suggestive of past binary interaction for this star.
