The Treaty of Waitangi is considered New Zealand's founding document, an agreement between the Crown and Maori, the country's indigenous people.
It was signed on February 6, 1840, at Waitangi in the Far North, by Governor William Hobson, on behalf of Queen Victoria, and the Maori chiefs who gathered there on that day. Eventually, around 540 chiefs, or rangatira, signed the Treaty.
However, a number of chiefs challenged the Crown's right to rule and refused to add their names.
The document itself has three articles, which lay out the principles on which the two groups would form a nation and build a government. It covers sovereignty, land and rights.
However, the English and Maori versions do not convey the same meaning. Essentially, Maori did not believe they were giving up their sovereignty; or their authority over their lands.
The conflicting interpretations have long been the subject of debate, and protest, as Maori argued for the terms of the document to be upheld. The differing views between Maori and the Crown are also believed to be one of the underlying causes of the Maori Wars.
The exclusive right to determine the meaning of the Treaty now rests with a commission called the Waitangi Tribunal, which investigates alleged breaches by the Crown. More than 2000 claims have been lodged and major settlements reached, aimed at righting land grievances of the past.
Since the 1970s, there has been a surge in awareness of what the Treaty means. Protest - at Waitangi, but also occupations like Bastion Point and Motoa Gardens, brought Maori greivances to the fore. In modern times, the wrongs done to Maori are more widely accepted and it is common to talk about the "spirit" or "intention" of the Treaty as viewed through a Maori lens.
Waitangi Day was first commemorated as a holiday in 1934, two years after Governor-General Lord Bledisloe and his wife bought and gifted to the nation the rundown house of James Busby, where the treaty was signed. Bledisloe hoped the day would become a celebration of the nation. The first Waitangi Day saw more than 10,000 Maori in attendance.
It took until 1947 for the commemorations to become an annual event, after the Royal New Zealand Navy erected a flagpole on the grounds to perform a ceremony. The ceremony featured no Maori, although a Maori speaker was added the next year. By the late 1950s the Prime Minister and Governor-General attended Waitangi regularly, and a Maori cultural performance was usually part of the day.
Waitangi Day was recognised as a national day by 1960, and became a regional Northland holiday by 1963. In 1974 It was made a nationwide public holiday under Norman Kirk's Labour Government and renamed New Zealand Day in a move towards a broader definition of nationhood. In 1976, when Rob Muldoon's National Government came into power, the new name was dropped because Muldoon "didn't like it". Many Maori supported this move, saying the name New Zealand Day denigrated the Treaty.
Some of the early features remain at modern Waitangi Day ceremonies, such as the naval salute, speeches from dignitaries and cultural performance.
Proceedings usually commence on February 5, at Te Tii Marae at the mouth of the Waitangi River (colloquially called the Lower Marae). Te Tii has long been a centre for debate on the treaty - in the 1880s major gatherings were held there to try to solve problems arising from land loss, to little avail.
Now, Te Tii is where politicians are welcomed to pay respects to local iwi. As in the past there are speeches, which are often political in nature, focusing on the events of the day. As such the lower marae can be a focus for protest.
The rest of the ceremony is held across a bridge at the Treaty grounds, which encompass Busby's former home, the flagstaff and the carved meeting house Te Whare Runanga, built for the 1940 celebration.
On February 6, the Royal New Zealand Navy raises the New Zealand Flag, Union Flag and White Ensign on the flagstaff in the Treaty grounds at dawn. During the day there is a church service, followed by dance and waiata.
Waka and the navy re-enact the calling ashore of Governor Hobson to sign the treaty. During this, the world's largest ceremonial war canoe, Ngatokimatawhaorua, is launched.
At the end of the day the flags are lowered.
Different perspectives on the holiday have been apparent since the first Waitangi Day. On that occasion, while the Crown was focused on unity, with Lord Bledisloe giving a speech about "one people", Maori took the opportunity to look back on their independent status.
Increasingly, Maori leaders used the occasion to make their voices heard by those in power who visited the site, and, as such, Waitangi has become a stage for debate. The first instance of this was in 1940, on the centenary of the Treaty, when Maori politician Apirana Ngata drew attention to Maori concerns over race relations in New Zealand. In a speech he observed that "not everyone had something to celebrate".
In the post-war era of the 1940s and 50s the debate quietened, and speeches dwelt on racial harmony and the unified nation. However by the 1970s the mood had changed again, to become more heated as understanding of the Treaty grew among a wider populace. The first protest was organised in 1971 by the activist group Nga Tamatoa. In 1973 members wore black armbands, to mourn the loss of land. They called the Treaty a "fraud" and had major clashes with police, resulting in dozens of arrests. The protests were aired across the country on televised broadcasts.
In the 1980s, the focus returned to calls to honour the Treaty and uphold its principles. The police presence remained, and by 1983 the commemoration was all but farce, with huge numbers of police in riot gear facing off with activists. Protestors wanted to raise concerns over land loss, but also wanted wider acceptance of Maori culture, sovereignty, an acknowledgement of their tangata whenu status and, as time went on, faster settlement of land claims.
What has been described as the "pinnacle" of Waitangi Day activism came in 1984.
A hikoi from Ngaruawahia to Waitangi was organised by Eva Rickard and Titewhai Harawira. The 4000-strong march included iwi, church leaders and some Pakeha. They made it to the Lower Marae, but were prevented from meeting Governor-General David Beattie. Activist group Te Kawariki began to protest at Waitangi in 1985, and this continued into the 2000s. Protest has been focused largely on the Lower Marae, but there have also been attempts to damage the flagstaff, harking back to when Hone Heke chopped down the British flagstaff in Russell in the 19th century.
Tensions at Waitangi aren't always between Maori and the Crown. Older leaders and young activists within Maoridom have frequently held different views on who should speak. In 1998, then-Leader of the Opposition Helen Clark was brough to tears when Titewhai Harawira challenged kaumatua for allowing a Pakeha woman to speak on the marae when Maori women could not.
Since the 1990s, the country's leaders have taken varying stances on attending Waitangi. As Prime Minister, Helen Clark was jostled in 2004 amid the Foreshore and Seabed controversy and did not return to the Lower Marae, although she continued to attend celebrations at the Treaty grounds. The same year, Leader of the Opposition Don Brash was hit with mud as he entered the marae.
Protest was expected to die down after 2006, when the newly-elected Maori Party won four seats in Parliament, because Ngapuhi leaders believed they finally had a voice in Parliament. However, it wasn't to be, and in 2009 John Key was manhandled at Te Tii, with two men later convicted of assault.
Debate continues to rage about the purpose of Waitangi Day, with some high-profile New Zealanders such as Paul Holmes labelling protestors "loonies". Responses to this have included numerous essays from Maori academics, including one in 2015 by historian Hirini Kaa, who explained how protest was "actually upholding a long and immensely patient movement for justice". Some believe Anzac Day should be the national day, or the holiday should be called New Zealand Day once more. Proponents say this would be "more like Australia Day" where the nation could "feel proud", go to the beach, and have fireworks. In 2015, there were also calls to also establish a separate Land Wars day, to commemorate those who died in the Maori Wars of the 1880s.
The Government has given funding to events that support Waitangi Day commemorations - from the money given to the ceremony at Waitangi itself, to tree-planting or kapa haka in various parts of the country. It is celebrated with parties by expatriates overseas. As the holiday falls in summer, many use the day to go to the beach. Maori communities often use the day to discuss the Treaty, and some marae have open days where the public can go to learn about New Zealand history.