Intersecting Histories II

See here.

Aeneas, Ythri And Vixen
In the 24th century, an Aenean Christian comes into conflict with the Ythrian New Faith on Avalon.
In the 25th century, Adzel meets Henry Kittredge from Vixen.
In the 29th century, Ythrian choths on Avalon accept human members and High Sky Choth mostly keeps to the Old Faith.
In the 31st century, Dominic Flandry meets Catherine Kittredge from Vixen and exiles Aenean rebels. Helen Kittredge from Vixen dies in combat.
In the 72nd century, a New Vixenite meets the Kirkasanter descendants of the Aenean exiles.

Thus:
human-Ythrian interaction develops;
the long history of human beings on Vixen, then on New Vixen, and the equally long history of human beings on Aeneas, then on Kirkasant, eventually converge.

Earth And Merseia
In the 25th century, the Polesotechnic League shields Merseia from supernova radiation.
In the 29th century, the Roidhunate of Merseia is a distant but growing threat.
In the 31st century, the Roidhunate has become the main adversary of the Terran Empire although Merseian settlers on the human colony planet of Dennitza are loyal to the Emperor, not to the Roidhun. Olaf Magnusson, raised to be pro-Merseian, tries to become Emperor.
In the mid-4th millennium, the Empire falls and we infer that the Roidhunate does also.

Thus:
not only human beings and Ythrians but also human beings and Merseians can share a planet;
we want to read a lot more of this history.