  We report the results of a spectroscopic investigation of a sample of 20 of
the brightest type 2 Seyfert nuclei. Our goal is to search for the direct
spectroscopic signature of massive stars, and thereby probe the role of
circumnuclear starbursts in the Seyfert phenomenon. The method used is based on
the detection of the higher order Balmer lines and HeI lines in absorption and
the Wolf-Rayet feature at $\sim$4680 \AA in emission. These lines are strong
indicators of the presence of young (a few Myrs) and intermediate-age (a few
100 Myrs) stellar populations. In over half the sample, we have detected HeI
and/or strong stellar absorption features in the high-order (near-UV) Balmer
series together with relatively weak lines from an old stellar population. In
three others we detect a broad emission feature near 4680 \AA that is most
plausibly ascribed to a population of Wolf-Rayet stars (the evolved descendants
of the most massive stars). We therefore conclude that the blue and near-UV
light of over half of the sample is dominated by young and/or intermediate age
stars. The ``young'' Seyfert 2's have have larger far-IR luminosities, cooler
mid/far-IR colors, and smaller [OIII]/H$\beta$ flux ratios than the ``old''
ones. These differences are consistent with a starburst playing a significant
energetic role in the former class. We consider the possibility that there may
be two distinct sub-classes of Seyfert 2 nuclei (``starbursts'' and ``hidden
BLR''). However, the fact that hidden BLRs have been found in three of the
``young'' nuclei argues against this, and suggests that nuclear starbursts may
be a more general part of the Seyfert phenomenon.
