This month we take another look at the Holy Roman Empire for our latest Almost Queen. The death of a sixteen year old Archduchess ultimately led to a marriage reshuffle that saw her youngest sister end up in France, raising the question of what might have happened had she survived.

When George William Frederick, Prince of Wales, became King George III of Great Britain in 1760, he instantly became the most eligible bachelor in Europe.

However the field of candidates was somewhat narrower than it had been for his medieval predecessors. There could no longer be a glorious match with a wealthy French princess or a well-connected Spanish infanta, because the bride had to be a Protestant. As a result George was confined to looking to Scandinavian candidates, and the young women of the German principalities.

It's rare that you have two shots at any crown, let alone the same crown – poor Margaret of Nevers missed both!

Getting a crown can be all about the timing. Catch one little bout of plague at the wrong time, or wave your husband off as he goes to fight an unwinnable battle, and suddenly you're no longer a prospective Queen! In this case Bonne managed to miss out on a French crown by a mere year, after seventeen years of marriage.

Most of our Almost Queens have been robbed of their prospective crown by death, either theirs or their husbands. In the case of Blanche of Burgundy, cousin of Margaret of Burgundy, it was divorce because of her adultery that stopped her getting the crown.

Getting an annulment for a marriage could be quite tricky, especially if a Pope decided not to play along. Pity poor Joan of Valois then, who was not only completely blameless but couldn't even hope to be defended by the Holy Father.

If becoming Queen of England was contingent on marrying King John, would you do it? Isabel of Gloucester didn't really have much choice in the matter, although to be fair at the time there was no suggestion that John would actually become King. It didn't matter in the end either as Isabel never got to be Queen!

Many princesses have missed out on the throne due to an early death, whether it was their death or that of their spouse. But in the case of Margaret of Burgundy she lost her chance at a crown due to a scandal that rocked the French court. More than that, her cousin Blanche came unexpectedly close to the crown too, and was brought down by the exact same scandal.

Technically an “Almost Empress” instead of an “Almost Queen”, Isabella of Parma came very close to becoming “Holy Roman Empress” before being struck down by smallpox.

I've mentioned before in this series that France went through a period of multiple “almost queens” across several generations. One of these was Marie Adelaide of Savoy, whose arrival at the French court at the age of ten seemed to signify a fresh new start for an elderly, war-weary court.

Caroline of Ansbach and Charlotte of Mecklenburg-Streilitz are the best known of the Hanoverian Queens. As the wives of, respectively, King George II and King George III, they wore the consorts crown. George I's wife Sophia had been imprisoned for years when he came to the throne, and George IV's wife Caroline of Brunswick was never crowned or recognised by her husband as Queen. William IV's wife Adelaide of Saxe-Meiningen is generally forgotten about, possibly because attention tends to focus more on her husband's battles over their niece, the future Queen Victoria.

But between Caroline and Charlotte should have been another Queen. The untimely death of George III's father, Frederick Prince of Wales, meant that his wife Princess Augusta of Saxe-Gotha suddenly went from Queen-in-Waiting to Dowager Princess of Wales, and would instead have to watch her daughter-in-law get the coronation she might otherwise have expected for herself.