Prince Albert II has been enthroned in the tiny principality of Monaco, ending a process that began when he was sworn in before his subjects in July.
Prince Albert says he will marry "when the time is right"
He blinked back tears as he was blessed by the archbishop of Monaco, Monsignor Bernard Barsi, at a Mass said in Monte Carlo's cliff-top cathedral.
He was told his destiny was to carry on the Grimaldi dynasty after 700 years.
But the day's events were not all ceremonies. He also attended a football match and an opera.
Foreign dignitaries and royalty, although no kings and queens, were at the Mass.
"By rising to the Grimaldi throne, Prince Albert finds his place in the continuity of this dynasty," the archbishop said between strains of organ music and Handel's Messiah.
Bells pealed out across the principality which was bathed in brilliant sunshine.
The formal transfer of power was held at the palace where the prince was presented with a royal banner bearing his emblem.
The prince then attended a football match between Monaco and St Etienne before dressing for the grand Monte-Carlo Opera to see a performance of Rossini's opera Voyage to Reims.
Aged 47, he was officially proclaimed ruler of Monaco in a day of celebrations in July.
It followed three months of mourning for his father Prince Rainier, who died in April at the age of 81 and is buried in the cathedral along with his wife, Hollywood actress Grace Kelly.
Prince Albert's initial investiture in July had threatened to be overshadowed by his admission that he had fathered an illegitimate child, Alexandre.
Previous to that, the tall, balding prince had been the least scandal-prone member of the Grimaldi dynasty, which has ruled the principality for some 700 years.
He was a bachelor who kept his private life private, despite rumours of liaisons with models and actresses.
On Friday, he told France's Europe 1 radio that he still hoped to marry one day, but only when "the time is right".
"I have never said that I wouldn't marry... I am in no hurry," he said.