In Greek mythology, Cronus (Kronos) was not as tyrannical as his father, Uranus (Ouranos)—at least not initially. The dynamic between the two generations of rulers defines the succession myth.
Uranus (Sky), the primordial ruler, imprisoned his own children—the Cyclopes (Brontes, Steropes, Arges) and the Hecatoncheires (Cottus, Briareos, Gyges)—deep within Tartarus, the abyss beneath the underworld. He hated them for their monstrous forms and feared their power. This act of suppressing his offspring within the earth (Gaia) caused Gaia immense physical pain and rage, sparking the first rebellion.
Cronus, the youngest Titan, castrated Uranus with a sickle (given by Gaia), freeing his siblings and becoming king. His reign was mythologized as the Golden Age—a time of peace, abundance, and justice where humans lived like gods without toil or laws. He was initially a benevolent, just ruler.
Fearful of a prophecy that he would be overthrown by his own son, Cronus swallowed each of his children at birth (Hestia, Demeter, Hera, Hades, Poseidon). This mirrors Uranus's imprisonment of children—inside the body instead of Tartarus. Rhea tricked him with Zeus, who later forced Cronus to disgorge his siblings and led the Titanomachy (War of the Titans) to overthrow him.
Uranus was the primordial tyrant (active, cruel imprisonment of innocents). Cronus began as a liberator and just king but degenerated into tyranny driven by paranoia. Neither was "good," but Uranus's tyranny was foundational and unprovoked; Cronus's was reactive and born of fear—though equally horrific in effect.