Upon his return to the Shire, Frodo helped clear out a criminal mob, led by his cousin, Lotho Sackville-Baggins, and the fallen wizard Saruman, that had taken over the region during his absence. He refused to draw his sword, however, and saw to it that any enemies captured were not killed. He never recovered from the physical, emotional and psychological wounds he had suffered during the War of the Ring, and was in particular taken ill on the anniversaries of his wounding on Weathertop and his poisoning by Shelob. He briefly served as Deputy Mayor of the Shire, but later resigned. Two years after the Ring was destroyed, Frodo as the Ring-bearer and Bilbo as the Ring-finder were accorded the special right to travel to Valinor — where Frodo might be healed and find peace — together with Gandalf, Elrond and Galadriel, the Keepers of the Three Rings. They boarded a ship at the Grey Havens and passed over the sea. Having no children of his own, Frodo left his estate, along with the Red Book of Westmarch, to Sam, who, according to Hobbit legend, followed Frodo across the sea sixty-one years later, following the death of his wife Rose (née) Cotton.
https://en.wikipedia.org/wiki/Frodo_Baggins