  We present 3000--10000 Ang HST/STIS long-slit spectroscopy of the bright
super star cluster A (SSC-A) in the dwarf starburst galaxy NGC 1569. The 0.05"
HST angular resolution allows, for the first time, to probe for spatial
variations in the stellar population of a ~ 10^6 M_sun SSC. Integrated
ground-based spectra of SSC-A have previously revealed young Wolf-Rayet (WR)
signatures that coexist with features from supposedly older, red supergiant
(RSG), populations. We find that the WR emission complexes come solely from the
subcluster A2, identified in previous HST imaging, and are absent from the main
cluster A1, thus resolving the question of whether the WR and RSG features
arise in a single or distinct clusters. The equivalent widths of the WR
features in A2 --- including the CIV 5808 complex which we detect in this
object for the first time --- are larger than previously observed in other WR
galaxies. Models with sub-solar metallicity, as inferred from the nebular
emission lines of this galaxy, predict much lower equivalent widths. On the
``clean'' side of A1, opposite to A2, we find no evidence for radial gradients
in the observed stellar population at 0.05"<R<0.40" (~0.5 to 5 pc), neither in
broad-band, low-resolution, spectra nor in medium-resolution spectra of the
infrared CaII triplet.
