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The open cluster NGC 7419 is known to contain five red supergiants and a veryhigh number of Be stars. However, there are conflicting reports about its ageand distance that prevent a useful comparison with other clusters. We intend toobtain more accurate parameters for NGC 7419, using techniques different fromthose of previous authors, so that it may be used as a calibrator for moreobscured clusters. We obtained Str\"omgren photometry of the open cluster NGC7419, as well as classification spectroscopy of ~20 stars in the area. We thenapplied standard analysis and classification techniques. We find a distance of4+-0.4 kpc and an age of 14+-2 Myr for NGC 7419. The main-sequence turn-off isfound at spectral type B1, in excellent agreement. We identify 179 B-typemembers, implying that there are more than 1200 $M_{\sun}$ in B stars atpresent. Extrapolating this to lower masses indicates an initial cluster massof between 7000 and 10000 Msolar, depending on the shape of the Initial MassFunction. We find a very high fraction (~40%) of Be stars around the turn-off,but very few Be stars at lower masses. We also report for the first time astrong variability in the emission characteristics of Be stars. We verifiedthat the parameters of the red supergiant members can be used to obtainaccurate cluster parameters. NGC 7419 is sufficiently massive to serve as atestbed for theoretical predictions and as a template to compare more obscuredclusters. The distribution of stars above the main-sequence turn-off isdifficult to accommodate with current evolutionary tracks. Though the presenceof five red supergiants is marginally consistent with theoretical expectations,the high number of Be stars and very low number of luminous evolved B starshint at some unknown physical factor that is not considered in currentsynthesis models.

NGC 7419 as a template for red supergiant clusters