Some wore headdresses adorned with feathers and birds' beaks, while others dressed in sarongs or brandished clubs at the meeting of more than 5,000 leaders from across the archipelago in the village of Tanjung Gusta.
The island nation is home to an estimated 50 to 70 million indigenous people, out of a population of 255 million, but tribespeople have long lived a precarious existence.
They often have no proof of ownership of the land their families have inhabited for generations, and conflicts regularly break out between people trying to defend their homelands and mining and plantation companies seeking to expand into them.
"We demand an immediate resolution of indigenous land conflicts across Indonesia and we want the indigenous tribes' existence and rights over their lands to be recognised," said Safwan, the leader of an indigenous community from North Sumatra province who goes by one name.
Addressing the congress as tribespeople took part in colourful rituals, Indonesia's Forestry Minister Siti Nurbaya Bakar pledged Widodo's recent move was "just the beginning".
"The state's official recognition over indigenous forests is not the end of the fight," she said.
There have been recent signs of hope, with President Joko Widodo pledging in December to return about 12.7 million hectares of customary lands to indigenous people, and kicking off the process by handing back over 13,000 hectares to nine communities.
But tribespeople are pushing authorities to move even faster, with indigenous leaders saying that some groups are in danger of dying out unless they receive more protection.
The congress, organised by Indonesian group the Indigenous People's Alliance of the Archipelago, happens every five years and runs over about a week.
Indigenous groups are commonly defined as those that retain economic, social and cultural characteristics that are different from those of the wider societies in which they live.