A little more than half a century ago, Vinayak Savarkar was on trial for his life, accused of conspiring with seven other men in the assassination of Mohandas K. Gandhi on Jan. 30, 1948.

The court acquitted Savarkar, citing insufficient evidence, but there was never much doubt about where his sympathies lay: A hard-line Hindu nationalist who wrote admiringly of Nazi Germany, he made no secret of his antipathy toward India's Muslim population or toward Gandhi, whose embrace of religious tolerance and diversity he saw as a threat to India's cultural purity.

Moreover, Savarkar was personally acquainted with Nathuram Godse, Gandhi's assassin and one of Savarkar's most devoted followers. Some historians still believe that Godse would not have committed the murder without a green light from Savarkar, who died in 1966.

But yesterday's suspect is today's hero. In a ceremony this afternoon, India's Hindu-nationalist government unveiled a portrait of Savarkar to hang opposite Gandhi's in the central hall of Parliament, describing him as a neglected and misunderstood patriot who deserves his place in the pantheon of India's great leaders.

The ceremony reflected the degree to which hard-line Hindu nationalism has moved into the mainstream of Indian politics, drowning out debate on other topics, such as development, and alarming those who see the movement as a threat to the secular, pluralistic nature of Indian democracy.

"All the political stigma has been cleared today," Savarkar's nephew, Vikram Savarkar, said after the ceremony, which was organized by the ruling Bharatiya Janata Party (BJP) and presided over by President Abdul Kalam. "He had been kept away from history books. Now his name will be everywhere."

That prospect is deeply disturbing to guardians of India's secular democratic traditions, among them leaders of the opposition Congress party, which boycotted the ceremony. Historians and civil-society groups joined the Congress party in denouncing the government's decision. Besides resurrecting questions about Savarkar's role in the Gandhi assassination, they cast doubt on his patriotism, citing evidence that he had collaborated with India's British colonial overlords and endorsed partition of the subcontinent into India and Pakistan at independence in 1947 -- an outcome still widely seen here as an avoidable tragedy.

"He has been a figure of shame all his life, and now his portrait will go here in Parliament?" said Vishwa Nath Mathur, 90, who was imprisoned by the British during the colonial era and appeared at a news conference Tuesday organized by opponents of the portrait-hanging. "Savarkar was essentially from the beginning a very weak character."

Spokesmen for the BJP and its parent organization, the National Volunteer Corps -- known as the RSS, the initials of its name in Hindi -- accused the Congress party leader, Sonia Gandhi, and other critics of distorting Savarkar's record for political purposes. On the charge that Savarkar was involved in Gandhi's assassination, they said the court acquittal speaks for itself. On the charge that he was unpatriotic, they released a 1980 letter from Prime Minister Indira Gandhi -- Sonia Gandhi's mother-in-law, but no relation to Mohandas Gandhi -- in which she praised Savarkar as a "remarkable son of India" who deserved to be celebrated for his "daring defiance of the British government."

Born in 1883 and a onetime student at London's Inns of Court, Savarkar spent years in a British penal colony for ordering the assassination of a British official. Although some later accused him of offering to cooperate with his jailers in exchange for leniency, he is revered among Hindu nationalists for his coinage of the term Hindutva -- literally, Hinduness -- at the center of the campaign by the RSS and its offshoots to shape India as a culturally homogeneous nation.

In one passage of his 1923 book, "Hindutva: Who Is a Hindu?" Savarkar seems to question the patriotism of India's minority Muslim and Christian communities: "[Muslim] or Christian communities possess all the essential qualifications of Hindutva but one . . . they do not look upon India as their holy land," he wrote. "Their holy land is far off in Arabia and Palestine. Consequently their names and their outlook smack of foreign origin. Their love is divided."

More controversial than Savarkar's writings was his association with the killers of Gandhi, whose peaceful protest movement is widely credited with forcing the British to leave India. Savarkar was the leader of a right-wing political organization, the Hindu Mahasabha, whose acolytes -- including Godse, Gandhi's slayer -- deeply resented what they saw as Gandhi's "appeasement" of India's Muslims.

Although Godse testified at his trial that Savarkar was not involved in the assassination, he and an accomplice, Narayan Apte, were regular visitors to Savarkar's Bombay home in the months leading up to the killing, according to evidence presented at the trial. Another accomplice, Digamber Badge, who turned state's evidence, testified that less than two weeks before the assassination, he had overheard Savarkar bidding Godse and Apte goodbye with the instruction, "Be successful and return."

Judge Atma Charan ultimately ruled that it would be "unsafe" to convict Savarkar without corroborating evidence.

At today's ceremony, lawmakers from the BJP and other parties in India's coalition government greeted the unveiling with shouts of "Long Live Savarkar," and "Long Live Mother India." Then they formed a line and took turns throwing rose petals on the portrait, bowing before they moved on.

"Today the picture is there -- the ideology will follow," said Vikram Savarkar. "This is just the beginning."

Special correspondent Rama Lakshmi contributed to this report.