Aboriginal elder and activist William Cooper was at his home in Footscray, Victoria when he learned about Nazi attacks on Jews in Germany.

On November 9-10, 1938, Jewish businesses, synagogues, houses and schools were destroyed, dozens of people were killed and 30,000 men were arrested and taken to concentration camps, in what is known as Kristallnacht — the night of broken glass.

It sent shockwaves through Europe and the rest of the world.

Having publicly condemned the mistreatment of Aborigines in Australia, the Yorta Yorta man could not stay silent.

A photo of William Cooper in 1935. ( Supplied: Museums Victoria )

On December 6, 1938, Mr Cooper led a delegation from his home to the German consulate in Melbourne to deliver a letter protesting against the violence.

When Mr Cooper and members of the Australian Aboriginal League arrived at the consulate, they weren't allowed inside, and the letter was passed on to a guard.

It is considered by many to be the only protest of its kind in the world at the time, according to the National Museum of Australia.

Mr Cooper's grandson, Uncle Alf (Boydie) Turner, said it was still unknown where the original letter went.

"Those letters, we couldn't figure out where they'd gone. I think they went in the wastepaper basket," Uncle Boydie said.

Letter finally delivered, almost 80 years on

Last year, the protest finally bore fruit.

With support from Melbourne's Jewish community, Uncle Boydie delivered a replica of his grandfather's letter to the German Government.

Uncle Boydie says his grandfather William Cooper was "a great man". ( ABC Goulburn Murray: Mahalia Dobson )

"We decided we would deliver it. It took us 10 years and we finally presented the letter to the German Government."

He said he felt both delighted and relieved that, almost 80 years on, he was able to continue his grandfather's crusade.

"I felt like something had been lifted off my shoulders," he said.

He was joined by the Jewish convenor of William Cooper's Legacy, Abe Schwarz, at the Australian embassy in Berlin.

"The German Government came, and they finally accepted the letter that was 79 years in the making to get there," Mr Schwarz said.

Abe Schwarz outside the old German embassy in Melbourne. ( Source: Danielle Bonica )

William Cooper's legacy

Despite its historical significance, William Cooper's story remains widely unknown.

"I always knew there was a story but people in Australia are just finding out about it," Uncle Boydie said.

Mr Schwarz said he was frustrated that Mr Cooper did so many incredible things yet wasn't considered a household name in Australia.

The William Cooper Justice Centre in Melbourne's legal district is named in honour of the Yorta Yorta leader. ( Source: Danielle Bonica )

"You know, it's almost unbelievable his name is not known. He did so many amazing activities to try to stand up for his own mob, let alone whilst he had no rights of his own, standing up for other people," he said.

"I don't believe he actually met a Jew in his life, but he knew what racism was and he knew how to act ethically. I think it was the humanity of the man; he knew what was right and what was wrong.

"When he read what was happening in Germany, he said if someone didn't stand up to Hitler, there would be genocide."

Uncle Boydie said Mr Cooper's fight for the Jewish cause demonstrated what a staunch advocate for human rights he was.

"He stood up because of the treatment of his own people, the Aboriginal people, and I think that's the main reason he stood up for the Jews."

Mr Schwarz said that in 1938, Mr Cooper was unknown to the Jewish community.

William Cooper's house at Footscray in Melbourne's west. ( Source: Danielle Bonica )

He said it wasn't until the early 2000s that his actions became known, and not on a larger scale until 2008, when 300 Jewish leaders and members of the Yorta Yorta community came together.

"The whole idea that someone stood up for us when we were being attacked by the Nazis wasn't known really before 2002," Mr Schwarz said.

"He is regarded as an amazing a hero in the community."

On the 80th anniversary of Kristallnacht, both Uncle Boydie and Mr Schwartz hope more people will learn about Mr Cooper and follow in his footsteps.

"Let's stand up for human rights in the way William Cooper did and let's ensure that racism never ever raises its ugly head again," Mr Schwartz said.