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We report on a long-lasting, elevated gamma-ray flux state from VER J0521+211observed by VERITAS, MAGIC, and Fermi-LAT in 2013 and 2014. The peak integralflux above 200 GeV measured with the nightly-binned light curve is $(8.8 \pm0.4) \times 10^{-7} \;\text{ph}\;\text{m}^{-2}\; \text{s}^{-1}$, or ~37% of theCrab Nebula flux. Multiwavelength observations from X-ray, UV, and opticalinstruments are also presented. A moderate correlation between the X-ray andTeV gamma-ray fluxes was observed, and the X-ray spectrum appeared harder whenthe flux was higher. Using the gamma-ray spectrum and four models of theextragalactic background light (EBL), a conservative 95% confidence upper limiton the redshift of the source was found to be z<=0.31. Unlike the gamma-ray andX-ray bands, the optical flux did not increase significantly during the studiedperiod compared to the archival low-state flux. The spectral variability fromoptical to X-ray bands suggests that the synchrotron peak of the spectralenergy distribution (SED) may become broader during flaring states, which canbe adequately described with a one-zone synchrotron self-Compton model varyingthe high-energy end of the underlying particle spectrum. The synchrotron peakfrequency of the SED, as well as the radio morphology of the jet from theMOJAVE program, are consistent with the source being anintermediate-frequency-peaked BL Lac object.

Multiwavelength Observations of the Blazar VER J0521+211 During an Elevated TeV Gamma-Ray State