  NGC 4945 contains a well-known heavily obscured active galactic nucleus (AGN)
at its core, with prior reports of strong nuclear and off-nuclear neutral Fe
K$\alpha$ emission due to the AGN activity. We report the discovery of very
extended Fe K$\alpha$ emission with the XMM-Newton EPIC pn in a $\sim5$ kpc by
$\sim10$ kpc region that is misaligned with the plane of the inclined optical
galaxy disk by $\sim60$ degrees in projection. After a careful consideration of
the crowded center of the galaxy and numerous unresolved hard X-ray sources
present, we estimate that $\sim15$% of the Fe K$\alpha$ is extended on
kpc-sized scales. The overall size and misalignment of the region follows an
unusual pattern of radio polarization that is not typical of starbursts or
normal disk galaxies but has been interpreted as possibly due to AGN activity.
We suggest that the extended Fe K$\alpha$ emission arose from a period of AGN
eruption several million years ago - a relic of a past AGN ejection episode.
