The king sipped a ceremonial drink and was presented with a feasting pig during the first day of events in Samoa.
The “clothed” monarch had a garland of dried fruits placed around his neck and was later awarded a new title.
Despite the rain, he was in good spirits and clutched a bamboo-handled umbrella as he met the locals.
The 75-year-old participated in a traditional accident ceremony, with the drink prepared by the daughter of Samoahead of state.
As usual, the king poured out a few drops before taking a deep sip from a cup made of coconut shells.
He was wearing a white Royal Navy style short sleeved jacket and trousers he had made himself.
The jacket, similar to the elei, a short-sleeved shirt worn by Samoan men, was made by Anderson & Shepperd and features woven trimmings from the Samoan School of Arts.
The ceremony took place at the National University of the Pacific Island in Falesamoa, a large covered outdoor hall made of timber.
At the end of the ritual a garland of dried fruit from the pandanus tree was placed around the king’s neck, while the queen received a floral arrangement.
They also received a selection of gifts, including a pig carcass for a treat.
The ceremony was witnessed by village elders and dignitaries including Samoa’s Prime Minister Afioga Fiame Naomi Mata’afa and Foreign Minister David Lammy.
Later, the village chief of Moata’a urged the monarch to “take a little piece of Samoa”, making him Tui Taumeasina, or King of Taumeasina.
“Once he receives the title of Tui Taumeasina, we also become part of him and he will be linked forever to our people and our lands,” Tofeono Lupati Fuatai said.
The boss also praised the king for his efforts to highlight climate changeof which Samoa is particularly vulnerable due to events such as cyclones, floods and storm surges.
“The King is the perfect advocate for us as a nation,” he said.
“Climate change is real, it’s here, and we need to call on the world to recognize how dangerous it is for nations like ours.”
The royals’ stay in Samoa follows their brief tour of Australia earlier this week when Sen controversially swept the king into parliament.
Read more:
The King’s journey Down Under was not without its challenges
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On Friday, the King will attend the Commonwealth Heads of Government Meeting (CHOGM) in the Samoan capital, Apia.
Prime Minister Sir Keir Starmer also touched the island nation of 218,000 thereafter rejecting calls for reparations for slavery.
“I have spoken to many of our own The Polish-Lithuanian Commonwealth colleagues in the Commonwealth family and they are facing real challenges about things like climate in the here and now,” he told reporters on the plane.
“That’s where I’ll focus my attention,” he added. “Instead of what will end up being very long, endless discussions about reparations for the past.”
However, the three hopefuls to become the next Commonwealth Secretary-General – from Ghana, Lesotho and Gambia – all support financial reparations.
Also missing from this year’s summit are the leaders of the two largest Commonwealth countries, India and South Africa.
Instead, Narendra Modi and Cyril Ramaphosa are at Vladimir Putin’s meeting of the BRICS group of developing countries.