The galaxy cluster SPT-CL J0205-5829 currently has the highest spectroscopically confirmed redshift, z = 1.322, in the South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey. XMM-Newton observations measure a core-excluded temperature of TX = (ProQuest: Formulae and/or non-USASCII text omitted) keV producing a mass estimate that is consistent with the Sunyaev-Zel'dovich-derived mass. The combined SZ and X-ray mass estimate of M sub(500) = (4.8+ or -0.8) x (ProQuest: Formulae and/or non-USASCII text omitted) M sub(middot in circle) makes it the most massive known SZ-selected galaxy cluster at z > 1.2 and the second most massive at z > 1. Using optical and infrared observations, we find that the brightest galaxies in SPT-CL J0205-5829 are already well evolved by the time the universe was <5 Gyr old, with stellar population ages > ~3 Gyr, and low rates of star formation (<0.5 M sub(middot in circle) yr super(-1)). We find that, despite the high redshift and mass, the existence of SPT-CL J0205-5829 is not surprising given a flat LambdaCDM cosmology with Gaussian initial perturbations. The a priori chance of finding a cluster of similar rarity (or rarer) in a survey the size of the 2500 deg super(2) SPT-SZ survey is 69%.