  Aims : We aimed at constraining the accretion-ejection phenomena around the
strongly-accreting Northern component of the S CrA young binary system (S CrA
N) by deriving its magnetic field topology and its magnetospheric properties,
and by detecting ejection signatures, if any.
  Methods : We led a two-week observing campaign on S CrA N with the ESPaDOnS
optical spectropolarimeter at the Canada-France-Hawaii Telescope. We recorded
12 Stokes I and V spectra over 14 nights. We computed the corresponding
Least-Square Deconvolution (LSD) profiles of the photospheric lines and
performed Zeeman-Doppler Imaging (ZDI). We analysed the kinematics of
noticeable emission lines, namely He I $\lambda 5876$ and the four first lines
of the Balmer series, known to trace the accretion process.
  Conclusions : The findings from spectropolarimetry are complementary to those
provided by optical long-baseline interferometry, allowing us to construct a
coherent view of the innermost regions of a young, strongly accreting star.
Yet, the strong and complex magnetic field reconstructed for S CrA N is
inconsistent with the observed magnetic signatures of the emission lines
associated to the post-shock region. We recommend a multi-technique,
synchronized campaign of several days to put more constrains on a system that
varies on a $\sim$ 1 day timescale.
