The recent history of work bearing on the early chemical/dynamical evolution of the Galaxy, and the relation of the halo population to the disk population(s) are discussed. In particular, the mean rotational velocity v(rot), and planar orbital eccentricity (e) are considered as functions of time, inferred from mean metallicity. For m/H less than about -1, signs of dynamicl evolution in mean v(rot) or mean e are not detected. It is argued that (e) for metal-poor stars is about 0.6, not 0.8 as previously believed, and is even lower in the three-dimensional case. It is pointed out that all the data are consistent with the high-velocity, low metallicity halo population having had a chemical and dynamical history almost independent of the Galactic disk. It is proposed that the halo was assembled from mergers of small satellites with the Galaxy along the lines discussed by Searle and Zinn (1978). It is further proposed that the Galactic bulge originated from the gaseous outflow from the Galaxy's halo and these fragments.
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Carney et al. (1990) studied this question.