A previous outburst of the eruptive star associated with the transient X-ray source A0620-00, first detected in August 1975, has been discovered on Harvard plates taken in 1917. The light curve of the earlier event is presented, and it is concluded that this star is a typical recurrent nova with an absolute magnitude of -5.9 (plus or minus 0.5) at a maximum brightness. The A0620-00 star has no detectable proper motion, and there appears to be little interstellar absorption. The best estimate of its distance is 11 plus or minus 3 kpc. A0620-00 is only 30.6 deg from the direction of the galactic anticenter and, therefore, must be located well beyond the detectable limits of our Galaxy.