The Long Life Of A Short Series

Poul Anderson's Kith series began publication in 1954 and completed publication in 1998, forty four years later. The series began with the specific premise of slower than light interstellar travel. Although Anderson showed scientific progress over the very long span of time covered by this future history, he did not compromise on that distinctive premise. There is plenty of FTL (faster than light) space travel in many of his other works.

The original story, "Ghetto," becomes a chapter in the 1998 novel. Thus, the author's 1954 vision of a possible future is incorporated into his much later view of a possible future. This is how future history writing works. Some revision of the texts is allowable but it is also good to see earlier and cruder concepts subsumed into maturer contexts. I am rereading some chapters of Starfarers with this in mind.

Interstellar trade is practiced by:

the Polesotechnic League in the History of Technic Civilization (FTL);
the Nomads in the Psychotechnic History (FTL);
the Kithmen in the Kith History (STL).

Nomads and Kithmen are alike in that they live in their ships.