Prince Harry and his fiancee Meghan Markle. Picture: AP

As Meghan Markle prepares to marry Prince Harry on Saturday, there's plenty to dissect: their relationship, her dress, the guests' fancy hats and all the royal traditions. But first let's take a moment to talk about what the former 'Suits' actress' title will be after she says 'I do'.

By tradition, male members of the Royal family receive a title from the monarch on their wedding day. After Saturday's nuptials, Meghan officially joins the British royal family, and just like her sister-in-law-to-be Kate Middleton, now known as the Duchess of Cambridge, she will have a new title bestowed on her when she makes the transition from 'commoner' to 'royal'. 

Although she will never be called Princess Meghan, her rank would be "princess by marriage of the United Kingdom, Great Britain and Northern Ireland."

Here are some of the predictions:

A likely contender is the Duke and Duchess of Sussex, a title that hasn’t been used since 1843.

There has only been one Duke of Sussex before, the sixth son of George III, and his two marriages were not approved by the king so there has never been a Duchess and his children were considered illegitimate.

The titles the Duke and Duchess of Clarence and Avondale are also an option.

However, the last Duke of Clarence, King Edward's eldest son, was also one of the suspects for Jack the Ripper.

Duke and Duchess of Buckingham is also an option, although it too has a long and fraught history,.

The third Duke of Buckingham was executed for treason against Henry VIII, while another died of a cold after chasing foxes, and the most recent in the 19th century was so unpopular that he had to suppress a major rebellion.

Another title mentioned is the Duke and Duchess of Connaught, which has been unused for 70 years. But it would be a controversial choice, as Connaught is in the Republic of Ireland.

Some have also speculated Prince Harry might become the Duke of Windsor. But the last Duke of Windsor was Edward VIII, who abdicated the throne to marry Wallis Simpson, so the Queen might not be too chuffed with the title.