Gandalf bears the title “the Grey” among Tolkien’s Istari.
Gandalf the Grey is one of the Istari, supernatural beings sent to Middle-earth to oppose Sauron. He appears as a wise wanderer and adviser, first helping the Dwarves and Bilbo in The Hobbit and later guiding the Free Peoples during The Lord of the Rings.
After falling with the Balrog in Moria, Gandalf returns in a transformed state as Gandalf the White. This change reflects his renewed authority and role rather than the arrival of a different character. He continues the struggle against Sauron and becomes a central leader in the War of the Ring.
Saruman is also an Istar, but he is known as Saruman the White at the beginning of the story. Radagast is associated with brown, and the other named Istari include the Blue Wizards, Alatar and Pallando. These titles distinguish their roles and identities.