Image copyright Iwasaki Shoten Image caption Yasuke depicted in a Japanese children's book by Kurusu Yoshio

Almost 500 years ago, a tall African man arrived in Japan. He would go on to become the first foreign-born man to achieve the status of a samurai warrior, and is the subject of two films being produced by Hollywood.

Known as Yasuke, the man was a warrior who reached the rank of samurai under the rule of Oda Nobunaga - a powerful 16th Century Japanese feudal lord who was the first of the three unifiers of Japan.

In 1579, his arrival in Kyoto, the capital at the time, caused such a sensation that people climbed over one another to get a glimpse of him with some being crushed to death, according to historian Lawrence Winkler.

Within a year, Yasuke had joined the upper echelons of Japan's warrior class, the samurai. Before long, he was speaking Japanese fluently and riding alongside Nobunaga in battle.

"His height was 6 shaku 2 sun (roughly 6 feet, 2 inches (1.88m)... he was black, and his skin was like charcoal," a fellow samurai, Matsudaira Ietada, described him in his diary in 1579.

The average height of a Japanese man in 1900 was 157.9m (5 feet 2 inches) so Yasuke would have towered over most Japanese people in the 16th Century, when people were generally shorter due to worse nutrition.

Making of a warrior

There are no records of Yasuke's date or country of birth. Most historians say he came from Mozambique but some have suggested other countries such as Ethiopia or Nigeria.

What is known, however, is that Yasuke arrived in Japan with an Italian Jesuit named Alessandro Valignano on an inspection tour, and appears in recorded history only between 1579 and 1582.

Some experts say he was a slave, but it is hard to say.

Floyd Webb and Deborah DeSnoo, filmmakers working on a documentary about him, believe assertions that he was a slave to be speculative at best.

"It would have been impossible for Yasuke to rise to the rank of a samurai in just a year without a warrior background," Ms DeSnoo says.

Samurais often began their training in childhood.

Friendship with the warlord

Yasuke met Nobunaga shortly after his arrival in Japan and he piqued his interest, the filmmakers say, by being a talented conversationalist.

Yasuke already spoke some Japanese and the two men got on well, according to academic Thomas Lockley, who has written a book on Yasuke.

According to Mr Lockley, Yasuke entertained Nobunaga with tales from Africa and India, where Mr Lockley believes Yasuke had spent some time before going to Japan.

Mr Webb believes that because of his command of the Japanese language, Yasuke would have been viewed favourably.

"He was unlike the Jesuits, who had a religious agenda for the soul of Japan," Mr Webb says.

There are reports that Nobunaga instructed his nephew to give Yasuke a sum of money at their very first meeting.

Image copyright Iwasaki Shoten Image caption Yasuke fighting alongside Oda Nobunaga in Kurusu Yoshio's children's book Kuro-suke

French-Ivorian writer Serge Bile was so intrigued by Yasuke's extraordinary rise that he wrote a book about the warrior.

"It's part of the mystery surrounding this character. That's why he fascinates me," he told the BBC.

The African warrior and the Japanese warlord had a lot in common.

Nobunaga was a great fan of the martial arts and spent a lot of time practising them. He was also an eccentric person, who according to Mr Webb, often dressed in Western-style clothes and sought the company of highly disciplined and intelligent people.

"[Yasuke] carried the warrior spirit," Mr Webb says. He understood the cultural language of Japan and loved to dance and perform Utenzi - a historic form of Swahili narrative poetry celebrating heroic deeds, Mr Webb adds. This suggests Yasuke could have come from Mozambique, as some historians believe, given that Swahili is still spoken in some northern parts of the country.

Similarly, Nobunaga was a lover of Noh Drama - a form of classical Japanese musical drama - and it is widely reported that he was a patron of the arts.

Nobunaga grew fond of Yasuke and treated him like family - the African was among a very select group of people allowed to dine with him.

"Nobunaga praised Yasuke's strength and stature, describing his might as that of 10 men," Ms DeSnoo says.

The legend lives on

When Nobunaga bestowed the rank of samurai on Yasuke the idea of a non-Japanese samurai was something unheard of. Later, other foreigners would also obtain the title.

As the first foreign-born samurai, Yasuke fought important battles alongside Oda Nobunaga.

Image copyright Getty Images Image caption French-Ivorian writer Serge Bilé has long been fascinated with Yasuke

He was also there on the fateful night one of Nobunaga's generals, Akechi Mitsuhide, turned against him and set the warlord's palace alight, trapping Nobunaga in one of the rooms. Nobunaga ended his own life by performing seppuku, a ritual suicide.

Before he killed himself, he asked Yasuke to decapitate him and take his head and sword to his son, according to historian Thomas Lockley. It was a sign of great trust.

The legend of Yasuke comes to an end shortly after this, in 1582. The fall of Nobunaga at the hands of a treacherous general resulted in the exile of the first black samurai, possibly back to a Jesuit mission in Kyoto.

Though his fate and the last years of his life remain unknown, Yasuke has lived on in the imaginations of many Japanese who grew up with the award-winning children's book Kuro-suke (kuro meaning "black" in Japanese) by Kurusu Yoshio.

The book, which dramatises Yasuke's life, ends with a bittersweet note: after Nobunaga kills himself, Kuro-suke (Yasuke) is taken to a temple where he dreams of his parents in Africa and weeps.

Entertainment industry newspaper Variety reported in May that Black Panther actor Chadwick Boseman is set to play Yasuke in a forthcoming feature film.

It will be the second Hollywood film being developed on the life of Yasuke.

In 2017, Hollywood studio Lionsgate announced it was developing a film on the life of the black samurai.

Nearly 500 years later, his unusual life continues to awe and inspire people.