More than 42,000 people gathered as the Hīkoi mō te Tiriti overflowed from Parliament's grounds and onto nearby Wellington streets.
Eru Kapa-Kingi told the crowd "Māori nation has been born" today and that 'Te Tiriti is forever'.
ACT leader David Seymour was met with chants of "Kill the bill, kill the bill" when he walked out of the Beehive for a brief appearance at Parliament's forecourt, before waving to the crowd and returning into the building.
The Treaty Principles Bill architect, Seymour, says he supports the right to protest, but thinks participants are misguided and have a range of different grievances.
See how the day unfolded with RNZ's live updates: