Multiple Historic Topo Maps to Georeference

I have multiple historic topo raster images [.jpg] which I have georeferenced to the ESRI standard topo base map and have created .mxd files for each map using ArcGIS Desktop 10.2.

I want to tile these georeferenced maps to create a single map to which I plan on adding various layers.

Being new to ArcGIS and, though, having read much material and watched a number of YouTube videos on ArcGIS topics that are close to what I need to do, but not quite, I would be very grateful for advice on the simplest approach to solving this problem.

Thank you very much,

Bill Cole
Fredericksburg, VA