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Circumstantial evidence suggests that merging played an important role in galactic evolution long before the present epoch. The key points of the argument can be summed up as follows:

  1. Starbursts and AGN are signposts of high-redshift mergers; the high incidence of such objects at z appeq 2 to 4 reflect frequent merging of juvenile galaxies.

  2. The bulk of the Milky Way's halo merged more than 10 Gyr ago as part of this activity.

  3. Cluster ellipticals merged before z appeq 2; their immediate progenitors were few and only moderately gassy.

  4. The metal-rich globular cluster systems of these ellipticals are relics of their final mergers.

Finally, direct observations of high-redshift events are complemented by archeological investigation of nearby systems. Both approaches are needed to discover what happened at redshifts z = 2 to 5.

I thank Alex Stephens and Hector Velázquez for communicating results in advance of publication. I also thank Jun Makino and the University of Tokyo for hospitality while I prepared this article. This research made use of NASA's Astrophysics Data System Abstract Service. Travel to the conference was covered by air miles accumulated while following the Grateful Dead.