The crowds filled a major traffic circle in the heart of the city and sprawled into its main thoroughfares.
The demonstrators waved “We Are Indonesia” signs and a giant red-and-white national flag was held aloft by hundreds of people.
The capital of Indonesia, the world’s most populous Muslim nation, has been rocked in the past month by two major protests against Gov Basuki ‘Ahok’ Tjahaja Purnama, who is being prosecuted for alleged blasphemy.
The movement against Ahok, who is the first ethnic Chinese to be governor of Jakarta and the first Christian in half a century, has raised communal tensions and challenged Indonesia’s reputation for practicing a moderate brand of Islam.
A demonstration against Ahok on Friday drew at least 200,000 people. An anti-Ahok protest on November 4 attracted at least 100,000 people and turned violent, with one dead and dozens of protesters and police injured.
Police say his detention is not necessary and have called for the legal process to be respected.
Sunday’s rally coincided with a weekly car-free morning in Jakarta when a central artery of the city is handed over to pedestrians for a few hours.
Police estimated 30,000 people turned up, said Jakarta police spokesman Argo Yuwono.
Organisers called it the “Parade of Indonesian Culture” and it featured traditional dances from Sabang in western-most Aceh to Merauke in eastern-most Papua.
National leaders of political parties under the pro-government coalition behind President Joko ‘Jokowi’ Widodo, an ally of Ahok, delivered short speeches on the importance of keeping the ethnically diverse nation united.
“We have to fight to materialise the aims of our independence. That will not happen if we are scattered, blaspheming, humiliating each other and no longer trust each other,” Surya Paloh, chairman of the National Democratic Party, said from the main stage.
“Our main enemies are stupidity and poverty. Therefore we ask the current government to work harder and always consistently with the people’s aspirations,” Paloh said.
Blasphemy is a criminal offense in Indonesia and punishable by up to five years in prison.