5 of the best Oprah Winfrey interviews of all time.

Over the past few days, a certain conversation has captured the world's attention: Prince Harry and Meghan Markle's interview with Oprah Winfrey.

On Monday night, 1.78 million Australians watched the two-hour tell-all "where no subject was off-limits", and got a greater insight into the royal family, the "institution" and the reasons why the couple walked away.

Watch: Prince Harry on Meghan Markle's mental health. Post continues after video.

But while Prince Harry and Meghan Markle were, for the most part, the centre of attention, viewers couldn't help but remember why the interview was so brilliant: Oprah.

Oprah Winfrey is undeniably an incredible celebrity interviewer. We saw that during this interview and in many of hers before. 

So let's revisit her best conversations.

Here are five of Oprah's best interviews of all time.

1. Fergie's Oprah Interview

Image: OWN. 

Let's start off with Oprah's other iconic royal interview with Sarah "Fergie" Ferguson. 

In 1996, the Duchess of York sat down with Oprah just after her split from Prince Andrew and famously declared that marrying into the royal family is "not a fairytale". 

"You didn't marry the fairytale, you married a man," she told Oprah. "You fell in love and married a man, and then you have to come to terms with the fairytale. Now it's not a fairytale, it's real life."

And similar to Princess Diana and Meghan Markle, Fergie openly discussed the negative aspects of the royal family. Specifically, how cruel the British press can be to those that marry into it.

"I must explain that the British press at the moment is completely and utterly cruel and abusive and so invasive. It is very cruel and very painful when you are going to try and find the feelings within to be on such a public stage," she said.

If you watched Harry and Meghan's interview and want to know more about the royal family, this tell-all is a must-watch.

2. Michael Jackson's Oprah Interview

Image: HBO.  In 1993, Oprah became the first person allowed to speak to the notoriously private performer, Michael Jackson, in 14 years.

During their conversation at Jackson's Neverland home, he opened up about his childhood, plastic surgery and changing skin colour, caused by the skin disease, vitiligo.

"It is something I cannot help. When people make up stories that I don't want to be who I am, it hurts me," he told Oprah. "It's a problem for me. I can't control it. But what about all the millions of people who sit in the sun to become darker, to become other than what they are. Nobody says nothing about that."

He also discussed his complicated relationship with his father, which was a sensitive subject for him. 

"I love my father, but I don't know him," he said.

3. Rihanna's Oprah Interview

Image: OWN. In 2009, shocking images surfaced of a viciously beaten Rihanna. Her boyfriend at the time, singer Chris Brown, had physically assaulted her and was sentenced to five years probation and given a restraining order against her.

Three years later, Oprah sat down with the singer for a rare interview in her home country of Barbados, to discuss the incident.

During the interview, Rihanna opened up about their relationship and explained why she forgave him.

"I think he was the love of my life. He was the first love and I see that he loved me the same way. We were very young and very spontaneous. We ran free. We ran wild. We were falling in love going in at a really rapid pace and we forgot about ourselves as individuals," she told Oprah.

"It was embarrassing, humiliating, hurtful," she said. "I lost my best friend."

4. Kim Kardashian's Oprah Interview

Image: OWN. In 2012, Kim Kardashian joined Oprah for a tell-all interview; and boy, did Oprah ask the hard-hitting questions.

During their conversation, Oprah asked about her infamous sex tape with Ray J and whether she'd be famous without it. 

"That was how I was introduced to the world. I'm aware, I'm not naïve to that fact," she said. "It was a negative way, so I felt like I really had to work ten times harder to get people to see the real me."

The talk show host also asked Kardashian about her 72-day marriage to basketball player Kris Humphries and whether it was all a publicity stunt. And Kardashian candidly responded.

"We have an amazing fan base - we don't do anything for ratings. Anyone who knows me knows I fall in love hard, I fall in love fast and I was in love," she said. 

Plus, Oprah spoke to other members of the family too. It's a great watch.

5. Tom Cruise's Oprah Interview

Image: OWN. 

And lastly, we can't forget the iconic moment when Tom Cruise declared his love for Katie Holmes and sort of... lost his mind.

In 2005, the actor joined Oprah for an interview, and he was so head-over-heels in love with Holmes that he jumped onto the couch with excitement.

Oprah repeated, "He's gone. He's gone. The boy is gone."

Honestly, you don't need to watch the entire interview, just those few minutes.

Feature image: OWN.