Bells rang out Thursday as Mexican President Felipe Calderon reenacted the moment 200 years ago when a priest urged his countrymen to rise up and overthrow their Spanish colonial masters.
"The moment of our emancipation has come," Calderon said, solemnly reiterating the words of priest Miguel Hidalgo y Costilla.
"The hour of our freedom has sounded and if you understand how valuable that is, you'll help me to defend it from the talons of the tyrants."
As the bells sounded, Calderon shouted out "Viva Mexico" - Hidalgo's cry from the pulpit of his church in the village of Dolores as he launched the 1810 uprising against the rule of Spain.
Eleven years later, in 1821, Mexico finally declared independence some three centuries after the arrival of the Conquistadors along the coasts of the New World in the 16th century.
A military parade later Thursday was to cap massive celebrations here, as Mexico seeks to briefly cast off the shadow of a bloody, pervasive drugs war and officially revive "the values and ideals that shaped our nation."
Troops from 17 countries - some of whom are also marking their bicentenary celebrations across the continent this year - were to join the parade along with units from China, France, Spain, Russia and the United States.
The festivities kicked off late Wednesday with a 40-million-dollar spectacle of fireworks, rock concerts and parades.
A group of shamans, in white robes and feathers, held a pre-Hispanic fire ritual to launch the celebrations in the capital's massive main Zocalo square, as millions joined nationwide fiestas.
The festivities have also been combined with celebrations for the centennial of the 1910-1917 revolution, when heroes like Emiliano Zapata and Pancho Villa overthrew the dictatorship of Porfiro Diaz.
But amid the general holiday atmosphere, some regions, hit by drug violence or devastating flooding, have scaled down their festivities.
Some 28,000 people have died in drug-related violence in the past three and a half years, according to official figures, with drugs gangs engaged in a bitter turf war also accused of car bombings and massacres of migrants.
Mexico's security forces are also under increasing scrutiny amid a military crackdown on organized crime, launched by Calderon in 2006, that has been matched by a severe spike in drug violence.
Some 74,000 security forces were deployed across the country, including snipers on Mexico City rooftops, to police the festivities, officials said.
In several violence-hit cities, including Ciudad Juarez, the country's most deadly town, the traditional independence ceremony was taking place behind closed doors for the first time, only to be shared with the public on television.
Fireworks will light up the sky of the border city, but crowds will be kept at least 500 meters (yards) away, said mayor Joses Reyes Ferriz.
The city of Morelia, in the western state of Michoacan, also held a subdued ceremony after suspected drug gang members lobbed grenades at an independence day crowd there two years ago, leaving eight dead.
Calderon's government has spent tens of millions of dollars on flashy projects, from road building to film making, while struggling to offer reassurances on concerns such as drug gang brutality and widespread corruption.
"The atmosphere of insecurity and violence which is closer and closer makes it complicated for many Mexicans to feel proud of the shape of the country at 200 years of independence," history professor Edgar Adrian Mora, from the Ibero-American University, told AFP.
A bicentennial monument and park are still unfinished and have increased criticism of the government's focus on flashy bicentennial projects, costing tens of millions of dollars, rather than on pressing issues such as poverty.
A slow recovery from the economic crisis and the worst rainy season on record, which has affected up to one million people this month alone, has further increased scrutiny of government spending.