Context : The number of known Be/X-ray binaries in the Large Magellanic Cloud is small compared to the observed population of the Galaxy or the Small Magellanic Cloud .
The discovery of a system in outburst provides the rare opportunity to measure its X-ray properties in detail .

Aims : IGR J05414-6858 was discovered in 2010 by INTEGRAL and found in another outburst with the Swift satellite in 2011 .
In order to characterise the system , we analysed the data from a follow-up XMM-Newton target of opportunity observation of the 2011 outburst and investigate the stellar counterpart with photometry and spectroscopy .

Methods : We modelled the X-ray spectra from the EPIC instruments on XMM-Newton and compared them with Swift archival data .
In the X-ray and optical light curves , we searched for periodicities and variability .
The optical counterpart was classified using spectroscopy obtained with ESO ’ s Faint Object Spectrograph at NTT .

Results : The X-ray spectra as seen in 2011 are relatively hard with a photon index of \sim 0.3–0.4 and show only low absorption .
They deviate significantly from earlier spectra of a probable type II outburst in 2010 .
The neutron star spin period of P _ { spin } = 4.4208 s was discovered with EPIC-pn .
The I -band light curve revealed a transition from a low to a high state around MJD 54500 .
The optical counterpart is classified to B0-1 IIIe and shows H \alpha emission and a variable NIR excess , vanishing during the 2010 outburst .
In the optical high state , we found a periodicity at 19.9 days , probably caused by binarity and indicating the orbital period .

Conclusions :