The Dalai Lama has arrived in Washington for an 11-day Buddhist ritual known as a kalachakra that organisers expect will draw more than 10,000 followers a day from America, Asia and Europe.
The elected prime minister of Tibet's government-in-exile, Lobsang Sangay, said the grand religious gathering would allow expatriates a right denied their brethren inside China - to meet their spiritual leader.
His visit begins on Wednesday with celebrations to mark his 76th birthday. He will also meet politicians during his stay, his longest in the US capital, although the White House has yet to announce if he will meet President Barack Obama.
Such a meeting would anger China, which accuses the Dalai Lama of seeking independence for Tibet. The Dalai Lama says he would accept autonomy for Tibet within China.
In May, the Dalai Lama relinquished his leadership of Tibet's government-in-exile, giving up the political power that he and his predecessors have wielded over Tibetans for hundreds of years.
Although he remains the spiritual leader of Tibetan Buddhism, his decision to abdicate his political role is one of the biggest upheavals in the community since the Chinese crackdown led him to flee in 1959 into exile in India.
The exile government will now to be led by Mr Sangay, a 43-year-old Harvard University legal scholar, who won an election in April. He grew up in a refugee camp, the son of a Tibetan Buddhist monk who took up arms against China after his monastery was destroyed.
Mr Sangay, who takes up his post next month, said continuing Chinese repression inside Tibet was a tragedy and urged continuing US support for Tibetan autonomy.
In recent months Chinese authorities have been accused of a crackdown at a prominent Tibetan monastery in Sichuan province, where in March a 21-year-old monk set himself on fire to protest at Chinese rule.
Mr Sangay said that while the kalachakra was not staged in Washington for political reasons, the gathering was an expression of a desire shared by Tibetans inside China.