Real Klingons are a loose faction of Klingons in the Klingon Empire . They are characterized by a belief in Klingon Supremacy. They believe that Klingons are the master race, destined to rule over all.
Opinions of non-Klingons vary between "Second Class Being" to "Kill them all", but are usually negative. Real Klingons assert that no true Klingon would tolerate the idea of a non-Klingon as Ally or Equal.
When New Klingons do this, Real Klingons have a severely negative reaction to it.
Real Klingons generally hold that Kahless II is a monster and utterly unfit for the Klingon Throne. There was a civil war over this and the Real Klingon side was soundly defeated, so open rebellion is not viable option.
Not all Real Klingon Houses and factions are the same. Some hold that any treachery or underhandedness is valid against Non-Klingonsm since Non-Klingons don't really count as people. Other Real Klingon aligned groups hold tight to honor, since they are the only ones preserving it.
Because of their hard core insistence that Klingons are the one true people. Real Klingon factions usually fall behind in terms of man power, productivity and economic power compared to New Klingon factions.
Although Real Klingons and New Klingons fight each other and enjoy fighting each other, its rare for a Real Klingon to actually put a New Klingon person in the "Not people" category. Real Klingons who do this are pretty extreme and usually on their way to a fall from power.