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We have conducted a search for $z\simeq7$ Lyman break galaxies over 8.2square degrees of near-infrared imaging from the VISTA Deep ExtragalacticObservations (VIDEO) survey in the XMM-Newton - Large Scale Structure (XMM-LSS)and the Extended Chandra Deep Field South (ECDF-S) fields. Candidate galaxieswere selected from a full photometric redshift analysis down to a $Y+J$ depthof 25.3 ($5\sigma$), utilizing deep auxiliary optical and Spitzer/IRAC data toremove brown dwarf and red interloper galaxy contaminants. Our final sampleconsists of 28 candidate galaxies at $6.5\le z \le7.5$ with $-23.5 \leM_{\mathrm{UV}} \le -21.6$. We derive stellar masses of $9.1 \le\mathrm{log}_{10}(M/M_{\odot}) \le 10.9$ for the sample, suggesting that thesecandidates represent some of the most massive galaxies known at this epoch. Wemeasure the rest-frame UV luminosity function (LF) at $z\simeq7$, confirmingprevious findings of a gradual decline in number density at the bright-end($M_{\mathrm{UV}} < -22$) that is well described by a double-power law (DPL).We show that quasar contamination in this magnitude range is expected to beminimal, in contrast to conclusions from recent pure-parallel Hubble studies.Our results are up to a factor of ten lower than previous determinations fromoptical-only ground-based studies at $M_{\rm UV} \lesssim - 23$. We find thatthe inclusion of $YJHK_{s}$ photometry is vital for removing brown-dwarfcontaminants, and $z \simeq 7$ samples based on red-optical data alone could behighly contaminated ($\gtrsim 50$ per cent). In comparison with other robust $z> 5$ samples, our results further support little evolution in the verybright-end of the rest-frame UV LF from $z = 5-10$, potentially signalling alack of mass quenching and/or dust obscuration in the most massive galaxies inthe first Gyr.

The bright end of the galaxy luminosity function at $z \simeq 7$ from the VISTA VIDEO survey