Boromir is mentioned in The Return of the Prince.
 Boromir's hubris makes him prey to the malign power of the Ring, and he seals his own doom when he attacks Frodo to seize it
Boromir had always planned to go to Minas Tirith, and despite the consensus reached at Rivendell that the Ring must be destroyed in Mordor, he urged the Fellowship to accompany him to Minas Tirith before going on to Mordor

