MONACO (Reuters) -- Prince Albert II of Monaco was enthroned Saturday, completing the formal succession in a process that began in July and marks the beginning of the playboy prince's reign of the tiny European principality.Albert, the 47-year-old son of Prince Rainier and Hollywood actress Grace Kelly, was sworn in as head of state in July after a three-month mourning period for his father, who died on April 6 at the age of 81 after having ruled for 55 years."Today is a day of joy in Monaco," Monsignor Bernard Barsi, the archbishop of Monaco, said during the ceremony at the Roman Catholic cathedral. The church was the site of Rainier's marriage to Grace, who was killed in a car crash in 1982.The archbishop said that Albert was a worthy heir to a dynasty that has led the principality for more than seven centuries. (Watch the ceremony -- 2:39)Revelations about the prince's love life, involving an admission that he had an illegitimate son with a French flight attendant of Togolese origin, had threatened to overshadow his investiture in July.About 900 people packed the cathedral, including foreign dignitaries and royalty, although no kings or queens attended.Monsignor Fortunato Baldelli, special envoy of Pope Benoit XVI, blessed a kneeling Albert as he and his sisters, Caroline and Stephanie, shed tears.Albert, who has been called one of Europe's most eligible bachelors, was born on March 4, 1958. Educated in Monaco and the United States, where he studied political science, he then worked in Paris and New York and served in the French Navy.He dreamt of a career in soccer, took part in the Paris-Dakar rally in 1985 and is a judo black belt. He represented Monaco at the Olympic Games in the bobsleigh four times and finished 7th in the world championships. He is a member of the International Olympic Committee.Copyright 2005 Reuters. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed.