The story of Prince Augustus, the only previous Duke of Sussex, is a tale of family breakdown, two illegal weddings and a heartbroken bookish and sensitive boy

As a wedding present HM The Queen gave her grandson the title of Duke of Sussex.

But if one looks back to the story of the first Duke of Sussex the honour might not have quite the prestige it should.

King George III and his wife Charlotte of Mecklenburg-Strelitz famously had a large family of 15 – including two future kings, George IV and his brother William IV. But the bond between the king and his children was famously difficult – and his relationship with his sixth son, Augustus, was no exception. Born in 1773 the ninth child of the royal couple was one of 13 children who lived to adulthood. Like Harry and Meghan he lived in Kensington Palace, although according to Janice Hadlow’s The Strangest Family – an in-depth account of the private life of the Hanoverians – he was packed off to the University of Gottingen at the age of 13, subsisting on just a guinea a week in pocket money. She refers to him as a “bookish and thoughtful boy” who suffered from asthma, and so didn’t make it into the navy like his brother William – dubbed the naval prince. His asthma attacks were so severe according to Hadlow that: “He was often unable to lie down to sleep at night, and was forced to try to rest sitting up in a chair.”

As a result the king decided Augustus’ career should be in the church and once his studies were over sent him to Rome for his health. It was there that Augustus would encounter the woman who would change his life. He met Lady Dunmore and her daughter Lady Augusta Murray outside the church of San Giacomo. His first act was to tie Lady Augusta’s shoelace for her. After that the two became intimate, reading The Tempest together, exchanging love letters where they referred to each other as Goosey and Gussy, and finally tying the knot on April 4 1793.

Unfortunately this wedding was in direct contravention of the 1772 Royal Marriages Act – which had been proposed by King George III after his brother Prince Henry, Duke of Cumberland and Strathearn, committed the unforgivable sin of marrying a commoner. Among its provisions the act, which was only repealed in the 2011 Perth Agreement, said that no descendant of King George II could marry without the consent of the reigning monarch.

When the king heard about the illegal marriage he summoned Augustus back to London. By the time he returned that autumn his new wife was pregnant. Augustus did take part in a second marriage ceremony in the December of that year, at St George’s in Hanover Square, while Lady Augusta was eight months gone, but this still didn’t cut any ice. The king sent Augustus back to Italy, having instructed the Lord Chancellor to “proceed in this unpleasant business as the law directs.”

On 14 July 1794 the Arches Court of Canterbury pronounced both marriages null and void, making Augustus’s son – who shared his father’s first name – illegitimate in the eyes of the law.

Shortly before his son was born Augustus wrote to his brother George saying: “My situation I believe to be one of the most unpleasant in the world… Many times has my mind been so overcome with despair that I have been almost distracted.” While in exile Augustus wrote several times to the king to plead for mercy, to muted or no response.

Hadlow’s sympathies for Augustus are clear. She describes him as an “inoffensive and affectionate man” who “cut a sad and solitary figure among the classical ruins of Rome.”

Conditions must have eventually thawed, as in November 1801 Prince Augustus Frederick had the title of Duke of Sussex conferred onto him – at the same time that his brother Adolphus was named the Duke of Cambridge. The title did not pass down to Augustus’s wife and two children though. The Duke and Augusta went their separate ways that same year.

It was not Augustus’s last entanglement with the Royal Marriage Act – in 1831 he married Lady Cecilia Gore. Once more he had failed to seek royal approval, but they stayed together until his death in 1843. According to Sarah Murden, blogger for the website All Things Georgian, the pair lived in Apartment 1 in Kensington Palace – part of which has since been readied for the new Duke and Duchess of Sussex.

Since Augustus’s death the title had remained vacant. Both of Augustus’s children died childless – Augustus in 1848 and Augusta in 1866 – meaning there is no unofficial duchy. There has never previously been a Duchess of Sussex – meaning Meghan Markle is the first to hold the title.

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