The basketball star, 25, and the actress, 32, became man and wife at a civil ceremony – as required by French law – at the Mairie (city hall for the 4th Arrondissement) in Place Baudoyer, not far from Notre Dame.
"They are married. They were married here by the Mayor of Paris, Monsieur Bertrand Delanoë," a spokesperson for the 4th Arrondissement district confirms.
Delanoë told PEOPLE of the couple he'd just married, "Their international reputations cannot escape me – but for me they are just Eva and Tony – two young people, very appealing, who love each other and who are at a very important moment in their life."
Just before 4:30 p.m. Paris time, wedding guests filtered out of the building and entered limousines. A large, white floral bouquet was placed in the rear of the stretch limo. The crowd, which had swelled to about 1,000, cheered loudly.
More on the Wedding
Earlier, Parker hosted a lunch for friends, who were ferried to the restaurant in three white stretch limos – including one Hummer – before returning to his hotel to dress for the ceremony.
Longoria and her family, meanwhile, visited the Chanel atelier for a final fitting. Clutching gift bags from the design house and wearing the Chanel ribbons and rosettes around their wrists, the group was then ferried to city hall, where hundreds of fans and dozens of reporters and photographers waited outside.
The bride's guests arrived in a Hummer with California plates around 2:45 p.m. Exactly four minutes later, Longoria stepped out of one of the other limos wearing a rose empire-waist minidress. (For the ceremony, she would wear a white tulle and sequin embroidered dress and tulle jacket by Chanel haute couture.)
She waved to cheering fans on her way into the building. The groom appeared just before 3, greeting officials amid a chorus of cheers and calls of "To-nee!"
With the civil service complete, the newlyweds will cement their union with a ceremony at the Church of Saint Germain l'Auxerriois on Saturday.
Invited guests – about 250 of them – include Desperate Housewives pals Teri Hatcher, Felicity Huffman, Nicollette Sheridan, James Denton, Ricardo Chavira and the show's creator Marc Cherry (Marcia Cross sent her regrets because she couldn't leave her twin babies).
Also expected are Parker's San Antonio Spurs teammates, coaches and friends, as well as Michael Douglas and wife Catherine Zeta-Jones and Jessica Alba and boyfriend Cash Warren.
Longoria and Parker got engaged in November and immediately made plans to have what her rep called a "big, happy ceremony with lots of family and friends" in Parker's native France.
Saturday's guests can look forward to a lavish reception at the Chateau of Vaux le Vicomte just outside Paris, where "the big color theme is red," says a source. "It's going to be a fairy-tale wedding."
Friday's ceremony capped off a week of partying, shopping and socializing, including a his-and-her bachelor party in St. Tropez. The newlyweds have been staying in an $11,000-a-night suite at the Park Hyatt Paris Vendome hotel.
"Paris is such a romantic city," says a source close to the couple. "They are so excited to get married there."
Reporting by PETER MIKELBANK, PETE NORMAN and COURTNEY RUBIN
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