In both
In the Beginning and the novel
To Dream in the City of Sorrows it is made clear that the Rangers have been in decline on Minbar for some time. They attract few recruits, especially from the Warrior caste, and most of their members are elderly. Members of the Gray Council privately mock the organization, and it is starved for funds and support.
When Sinclair takes over enough Minbari are convinced by events that there might be something to prophecy after all, and that the Rangers need to be reactivated, but there is still resistance. (As late as "Severed Dreams" the Gray Council is still split over whether or not the current troubles really indicate the return of the ancient enemy, and even over their belief in Valen's prophecies.) Having a Human at the head of the organization doesn't help any. Many Minbari who might be inclined to join the Rangers refuse because an alien is running the show. So a great many of Sinclair's recruits (Marcus and his brother are among the earliest) are Humans.
Until season 5, we don't see many Minbari Rangers. The ones we do see are mostly
new recruits who have joined since the Shadow war. The elderly trainers are from the pre-Sinclair era, and so are mostly Minbari. But the bulk of the Ranger force and hierarchy that actually saw service during the Shadow War were Human. They will, in the natural course of things, hold most of the senior command slots as the organiztion expands under the IA. And since the Rangers are now open to all races, odds are the Humans will remain the single largest contingent in the organization for some time to come.
I would also think that Humans would still be heavily recruited in the years after 2262. The independence of Mars, and possibly Proxima and Rigel, was ultimately won by Sheridan's fleet. Martian patriots and others would have an interest in supporting IA. There are probably still many refugees from Clark who aren't comfortable going home and who would be looking for someone or something to "serve" and "trust," There are probably also lots of military and ex-military personnel who followed orders under Clark, but aren't happy about the things they did. A stint in the Rangers could represent a kind of pennance for them.
After the Drakh plague and the quarantine of Earth, there will be a lot more Humans who "can't go home" and would want to serve in the Rangers to help look for a cure.
So I think. for a time at least, the Rangers will be dominated by, if not mostly made up of, Humans. (And don't forget, since the Rangers' rebirth under Sinclair, every leader of the Rangers that we see is human - either wholly or on a genetic level: Sinclair, Delenn, Sheridan and Ivanova.)
Regards,
Joe
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Joseph DeMartino
Sigh Corps
Pat Tallman Division
joseph-demartino@att.net
[This message has been edited by Joseph DeMartino (edited June 03, 2001).]