By the middle of February (1823) he had completed The Island; or Christian and his Comrades (published June 26, 1823). The sources are Bligh's Narrative of the Mutiny of the Bounty, and Mariner's Account of the Tonga Islands. Satire and tale are a reversion to his earlier method. The execution of The Island is hurried and unequal, but there is a deep and tender note in the love-story and the recital of the "feasts and loves and wars" of the islanders. The poetic faculty has been "softened into feeling" by the experience of life.

When The Island was finished, Byron went on with Don Juan. Early in March the news reached him that he had been elected a member of the Greek Committee, a small body of influential Liberals who had taken up the cause of the liberation of Greece. Byron at once offered money and advice, and after some hesitation on the score of health, determined "to go to Greece." His first step was to sell the "Bolivar" to Lord Blessington, and to purchase the "Hercules," a collier-built tub of 120 tons. On the 23rd of July the "Hercules" sailed from Leghorn and anchored off Cephalonia on the 3rd of August. The party on board consisted of Byron, Pietro Gamba, Trelawny, Hamilton Browne and six or seven servants. The next four months were spent at Cephalonia, at first on board the "Hercules," in the harbour of Argostoli and afterwards at Metaxata. The object of this delay was to ascertain the real state of affairs in Greece. The revolutionary Greeks were split up into parties, not to say factions, and there were several leaders. It was a question to which leader he would attach himself. At length a message reached him which inspired him with confidence.

He received a summons from Prince Alexander Mavrocordato, a man of birth and education, urging him to come at once to Missolonghi, and enclosing a request from the legislative body "to co-operate with Mavrocordato in the organization of western Greece." Byron felt that he could act with a "clear conscience" in putting himself at the disposal of a man whom he regarded as the authorized leader and champion of the Greeks. He sailed from Argostoli on the 29th of December 1823, and after an adventurous voyage landed at Missolonghi on the 5th of January 1824. He met with a royal reception. Byron may have sought, but he did not find, "a soldier's grave." During his three months' residence at Missolonghi he accomplished little and he endured much. He advanced large sums of money for the payment of the troops, for repair and construction of fortifications, for the provision of medical appliances. He brought opposing parties into line, and served as a link between Odysseus, the democratic leader of the insurgents, and the "prince" Mavrocordato. He was eager to take the field, but he never got the chance. A revolt in the Morea, and the repeated disaffection of his Suliote guard prevented him from undertaking the capture of Epacto, an exploit which he had reserved for his own leadership.

He was beset with difficulties, but at length events began to move. On the 18th of March he received an invitation from Odysseus and other chiefs to attend a conference at Salona, and by the same messenger an offer from the government to appoint him "governor-general of the enfranchised parts of Greece." He promised to attend the conference but did not pledge himself to the immediate acceptance of office. But to Salona he never came. "Roads and rivers were impassable," and the conference was inevitably postponed.

His health had given way, but he does not seem to have realized that his life was in danger. On the 15th of February he was struck down by an epileptic fit, which left him speechless though not motionless. He recovered sufficiently to conduct his business as usual, and to drill the troops. But he suffered from dizziness in the head and spasms in the chest, and a few days later he was seized with a second though slighter convulsion. These attacks may have hastened but they did not cause his death. For the first week of April the weather confined him to the house, but on the 9th a letter from his sister raised his spirits and tempted him to ride out with Gamba. It came on to rain, and though he was drenched to the skin he insisted on dismounting and returning in an open boat to the quay in front of his house. Two hours later he was seized with ague and violent rheumatic pains. On the 11th he rode out once more through the olive groves, attended by his escort of Suliote guards, but for the last time. Whether he had got his deathblow, or whether copious blood-letting made recovery impossible, he gradually grew worse, and on the ninth day of his illness fell into a comatose sleep.

It was reported that in his delirium he had called out, half in English, half in Italian, "Forward - forward - courage! follow my example - don't be afraid!" and that he tried to send a last message to his sister and to his wife. He died at six o'clock in the evening of the 19th of April 1824, aged thirty-six years and three months. The Greeks were heartbroken. Mavrocordato gave orders that thirty-seven minute-guns should be fired at daylight and decreed a general mourning of twenty-one days. His body was embalmed and lay in state. On the 25th of May his remains, all but the heart, which is buried at Missolonghi, were sent back to England, and were finally laid beneath the chancel of the village church of Hucknall-Torkard on the 16th of July 1824. The authorities would not sanction burial in Westminster Abbey, and there is neither bust nor statue of Lord Byron in Poets' Corner.

The title passed to his first cousin as 7th baron, from whom the subsequent barons were descended. The poet's daughter Ada (d. 1852) predeceased her mother, but the barony of Wentworth went to her heirs. She was the first wife of Baron King, who in 1838 was created 1st earl of Lovelace, and had two sons (of whom the younger, b. 1839, d. 1906, was 2nd earl of Lovelace) and a daughter, Lady Anne, who married Wilfrid S. Blunt (q.v.). On the death of the 2nd earl the barony of Wentworth went to his daughter and only child, and the earldom of Lovelace to his half-brother by the 1st earl's second wife.