  Deep long-slit spectroscopic data are presented for a sample of 14 3CR radio
galaxies at redshift z ~ 1, previously studied in detail using the Hubble Space
Telescope, the Very Large Array, and UKIRT. Analysis of the [OII] 3727 emission
line structures at 5 Ang spectral resolution is carried out to derive the
kinematic properties of the emission line gas. In line with previous, lower
resolution, studies, a wide variety of kinematics are seen, from gas consistent
with a mean rotational motion through to complex structures with velocity
dispersions exceeding 1000 kms. The data confirm the presence of a high
velocity gas component in 3C265 and detached emission line systems in 3C356 and
3C441, and show for the first time that the emission line gas in the central
regions of 3C324 is composed of two kinematically distinct components. Emission
line fluxes and the colour of the continuum emission are determined down to
unprecedently low observed wavelengths, lambda < 3500 Ang, sufficiently short
that any contribution of an evolved stellar population is negligible. An
accompanying paper investigates the variation in the emission line ratios and
velocity structures within the sample, and draws conclusions as to the origin
of the ionisation and kinematics of these galaxies.
