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Age, metallicity and spatial distribution of globular clusters (GCs) providea powerful tool to reconstruct major star-formation episodes in galaxies. IKNis a faint dwarf spheroidal (dSph) in the M81 group of galaxies. It containsfive old GCs, which makes it the galaxy with the highest known specificfrequency (SN=126). We estimate the photometric age, metallicity and spatialdistribution of the poorly studied IKN GCs. We search SDSS for GC candidatesbeyond the HST field of view, which covers half of IKN. To break theage-metallicity degeneracy in the V-I colour we use WHT/LIRIS Ks-bandphotometry and derive photometric ages and metallicities by comparison with SSPmodels in the V,I,Ks colour space. IKN GCs' VIKs colours are consistent withold ages ($\geq\!8$ Gyr) and a metallicity distribution with a higher mean thantypical for such a dSph ([Fe/H$]\!\simeq\!-1.4_{-0.2}^{+0.6}$ dex). Theirphotometric masses range ($0.5 <{\cal M_{\rm GC}}<4\times10^5M_\odot$) impliesa high mass ratio between GCs and field stars, of $10.6\%$. Mixture modelanalysis of the RGB field stars' metallicity suggests that 72\% of the starsmay have formed together with the GCs. Using the most massive GC-SFR relationwe calculate a SFR of $\sim\!10M_\odot/$yr during its formation epoch. We notethat the more massive GCs are closer to the galaxy photometric centre. IKN GCsalso appear spatially aligned along a line close to the IKN major-axis andnearly orthogonal to the plane of spatial distribution of galaxies in the M81group. We identify one new IKN GC candidate based on colour and PSF analysis ofthe SDSS data. The evidence towards i) broad and high metallicity distributionof the field IKN RGB stars and its GCs, ii) high fraction and iii), spatialalignment of IKN GCs, supports a scenario for tidally triggered complex IKN'sSFH in the context of interactions with galaxies in the M81 group.

Optical-NIR analysis of globular clusters in the IKN dwarf spheroidal: a complex star formation history