So how much of the late royal's shattering marriage woes have been truthfully translated onto the small screen?
The previous season saw Princess Margaret marry photographer Anthony Armstrong-Jones after her whirlwind romance with divorcé Peter Townsend became a matter of not only family but national dispute.
Following pressures from Churchill's government, Townsend was dispatched to Brussels where he would remain for two years. After learning that he was preparing to marry a 19-year-old woman, Marie-Luce Jamagne, via letter (break-ups weren't much better in the pre-text era either, huh?), Princess Margaret understandably acted out.
Cue dramatic scenes of the royal, brilliantly played by Vanessa Kirby, unfold on screen with her knocking back dainty bottles of alcohol and trashing her royal chambers to the horror of staff members.
Determined to grace the aisle first, she promptly accepted an invitation to wed photographer Armstrong-Jones - a romance which saw the royal physically (and metaphorically) escape the constraints of regal responsibilities on the back of a motorcycle.
Armstrong-Jones, later known as Lord Snowdon, soon became the first non-aristocrat to marry into the royal family in over 400 years but the run-up to the nuptials began to shed light on cracks in their relationship.
The second installment teased rumours of the photographer's love child with Camilla Fry, his friend Jeremy's wife, who was born just three weeks into his and Princess Margaret's honeymoon. But it wasn't until 2004 that Armstrong-Jones was confirmed the father through a DNA test.
Fast-forward to season three and Princess Margaret's love life is growing even more complicated, as the cult drama series addresses infidelities on both sides of the marriage.
Speculation of extramarital affairs first graced the headlines a few years into their marriage with The Telegraph suggesting that Lord Snowdon was "the first to be unfaithful" due to his long business trips overseas. While Princess Margaret embarked upon her first affair with landscape developer Antony Barton in 1966 while her husband was in India.
In February 1974, the royal invited him to her villa on the Caribbean island of Mustique and a photograph of the couple together was plastered on the front page of the News of the World - outing their relationship to the public. The royal family had no choice but to issue a statement in response acknowledging the end of her marriage to Lord Snowdon.
"HRH the Princess Margaret, Countess of Snowdon, and the Earl of Snowdon have mutually agreed to live apart. The Princess will carry out her public duties and functions unaccompanied by Lord Snowdon. There are no plans for a divorce proceeding," the Kensington Palace announcement read.
Despite their relationship coming under immense media scrutiny, Princess Margaret and Llewellyn's romance bloomed into an eight-year relationship which continued after her highly-publicised divorce from Lord Snowdon in 1978.
Before stepping into the Princess' polished shoes, Bonham Carter met Llewellyn to garner further insight into what really went on behind closed doors.
"He said they found each other just at the right time,” the actress continued. "They were both very lost, both felt somewhat outsiders, just not quite accepted by the family - or not quite good enough. Her confidence was really undermined by the breakdown of her marriage. He also gave her fun at a time when she hadn’t been having much."
Season three of The Crown is now available to watch on Netflix.