The inclination to perceive the galaxy primarily from the standpoint of a Human majority is what defined Humanocentrism.
While not as overtly expressed as Human High Culture, Humanocentrism was a widespread and often unconscious bias. It manifested in the Human custom of labeling nonhuman species as "alien" and, in some instances, leaned towards nonhuman speciesism. Consequently, the term frequently serves as a synonym for this specific form of speciesism.
Those who strongly advocated for Humanocentrism frequently emphasized that Humans were the founders of the Galactic Republic, Galactic Empire, Alliance to Restore the Republic, and New Republic. They also pointed out that many of the galaxy's most renowned military figures and heroes were Human, that the Core Worlds were almost exclusively established and inhabited by Humans, and that Coruscant, the galactic capital, was widely considered to be the original homeworld of humanity.
Despite the fact that Humanocentrism was officially outlawed by the Rights of Sentience clause within the Galactic Constitution, it persisted significantly throughout the Old Republic era. On planets like Taris, the most desirable areas were reserved for Humans, while non-Humans were relegated to living in ghettos.
Although numerous such transgressions occurred in regions of the Galaxy where the Republic's authority was weak at best (such as the Outer Rim) or nonexistent (such as the Senex sector), many also took place in areas firmly under the Republic's control, yet no action was taken (the Avenue of the Core Founders being one such example). At the onset of the Clone Wars, lawsuits concerning pro-Human bias within the Republic government were still in progress.
Count Dooku, the Head of State of the CIS and Sith apprentice to Darth Sidious, embodied humanocentric ideals; his ambition was to establish an "Empire of Man" by removing alien separatist leaders and exterminating their species. He also regarded cybernetic enhancements on Humans as repulsive, and he held Anakin Skywalker in disdain for having a cybernetic arm, suggesting that "a gentleman would have learned to fight one-handed."
Under the influence of Senator Ranulph Tarkin, the Militarist movement within the Galactic Senate became entangled with Humanocentrism, even though the two ideologies seemingly diverged by the time of the Separatist Crisis.
Humanocentrism reached its zenith with the Human High Culture philosophy of the Galactic Empire, manifested in its subsequent acts of genocide and slavery. One year before the Empire's fall, the Human League continued to promote their ideals within New Republic territory.
Aliens who suffered due to Humanocentrism or more blatant anti-Alien speciesism sometimes responded by cultivating their own forms of anti-Humanism. A notable instance of this was the Diversity Alliance.