President Raul Castro, who took over when his brother fell ill in 2006, was the last speaker and praised Fidel's accomplishments and character, especially in standing up to the United States.
Fidel Castro, he said, showed it was "possible to firmly maintain the inalienable principles of our sovereignty without fear to the nuclear blackmail of the United States during those days of the missile crisis in October 1962."
Despite his fame, Fidel Castro insisted "until the very last hours of his life" that no parks or public spaces be named after him and no statues or monuments be built in his honor, Raul Castro said.
"That's our undefeated Fidel, who calls us with his example and ... demonstrated that yes, we could; yes, we can; and yes, we will," Raul Castro said.
"Yo soy Fidel"
Castro's invitation-only funeral is scheduled for Sunday, so the Santiago memorial was the last chance for the masses to show their love for Castro.
The crowd gathered hours before the actual event began, chanting, "Yo soy Fidel!" (I am Fidel). Above them loomed the 16-meter (52.5-foot) statue of a Cuban freedom fighter from the 1890s, Antonio Maceo Grajales
Fidel Izaguire Martinez, 8, visited the square before the rally, carrying a small Cuban flag.
"He was the most important man in the country," the youngster said of his namesake.
World leaders, including some inspired by the Cuban revolution, paid their respects.
Dignitaries on the stage from Latin America included Venezuelan President Nicolas Maduro, Bolivian President Evo Morales, Ecuadorian President Rafael Correa, Panamanian President Carlos Varela, Nicaraguan President Daniel Ortega and Colombian President Juan Manuel Santos.
A FARC delegation and ex-Presidents of Brazil Luiz Inácio Lula da Silva and Dilma Rousseff also attended.
From Africa, Zimbabwean President Robert Mugabe and South African President Jacob Zuma joined the group.
Soccer legend Diego Maradona also spoke.
Castro's ashes arrived Saturday in Santiago after a four-day tour across the island nation. A military jeep pulled a trailer displaying the casket.
Starting in Havana, the tour reversed the route Castro took
across the island after seizing power in 1959. Crowds of Cubans lined the roads and stood on rooftops to watch Castro's funeral cortege pass by.
Santiago, Cuba's second-largest city, played a crucial role in Castro's rise.
On July 26, 1953, Castro led a group of about 150 rebels who attacked the Moncada military barracks in an unsuccessful attempt to overthrow the dictator Fulgencio Batista.
Castro was imprisoned briefly, but the attack made him famous and helped launch another, successful attempt to overthrow Batista. Castro declared victory January 1, 1959, from the balcony of the Santiago City Hall.
Perhaps as a reminder, a large black-and-white image of Castro wearing his familiar military fatigues and a backpack was projected on a screen beside the square in Santiago.
Castro died November 25
at 90, his brother announced on state television. Castro's remains were cremated Wednesday and hundreds of thousands attended a Mass that night in Havana.
The funeral will be at the eastern city's Santa Ifigenia Cemetery
where Jose Marti, the Cuban revolutionary leader from the 19th century, is buried. In attendance will be an unlikely mix of world leaders, royalty, Marxist guerrillas and Hollywood actors.
Though President Barack Obama reopened relations with Cuba this year, no representative from the United States government is expected.