As the nearest giant elliptical galaxy, NGC 5128 (Centaurus A) is an excellent place to use globular clusters (GCs) and host galaxy field stars to study galaxy evolution. We have performed a detailed investigation of this galaxy, comparing field star kinematics with the metallicities, ages, and kinematics of GCs. We used our sample of 780 planetary nebulae (PNe) to trace the kinematics of the field star population. Our survey for GCs bring the total number of confirmed GCs to 215. Using spectra of the brightest GCs to determine ages, we find that the metal-rich GCs have a mean age of approximately 4-5 Gyr, and that their kinematics are similar to those of the PNe. The metal-poor GCs have old ages similar to the Galactic GCs, and show a weaker kinematic correlation with the field stars. It is possible that NGC 5128 was formed by the merger of two or more disk galaxies at the time that the metal-rich clusters were formed.