How important were crowns as a symbol of power and were they passed down through a dynasty? I’ve always thought that crowns would hold great significance to both the small folk and nobility of a monarchy, and would be held up as evidence that the current ruler has a physical link to a line of previous kings (which the Iron Throne may do for Westeros). I’ve always found it strange that Renly so willingly wore a new crown blatantly featuring the Tyrell heraldy instead of wanting to claim Robert’s.

Crowns were very important as symbols, and they often were passed down, even across dynasties.

However, it was very rare for monarchies to only have the one crown, because the oldest crowns were usually too valuable and heavy to be worn every day. The result is that you get multiple crowns and thus multiple symbols, which GRRM’s notes on the Amok portraits of the Targaryens does a good job of laying out for the Targaryen dynasty.

I’m sure that Renly would have loved to have Robert’s crown to use, but that was never going to happen base on how Robert’s death went down. However, I don’t find it strange at all that Renly combined the Baratheon heraldry with the Tyrell heraldry:

The slender circlet around his brows seemed to suit him well. It was soft gold, a ring of roses exquisitely wrought; at the front lifted a stag’s head of dark green jade, adorned with golden eyes and golden antlers.
The crowned stag decorated the king’s green velvet tunic as well, worked in gold thread upon his chest; the Baratheon sigil in the colors of Highgarden.

For all his faults, Renly is someone who understands political symbolism, so this isn’t an accident. Rather, it’s a bit of quid-pro-quo to reassure the Tyrells that Renly is the path to a Tyrell on the Iron Throne, and to reassure the lords of the Reach that swearing allegiance to Renly is like swearing allegiance to the Tyrells, and you’ve already done that, so everything’s copacetic.

How does an imperial crown differ from a regular crown?

Glad you asked!

An imperial crown is closed, comme ca:

The loops of metal over the top, the globe on top, all of these things signify an imperial crown. The symbolic meaning is that the wearer recognized no authority beyond them (save God) – more on this in a second.

By contrast, a merely royal crown is an open circlet or diadem, comme ca:

Not to say that royal crowns – like this one, the famed Iron Crown of Lombardy used by Charlesmagne and Napoleon – couldn’t be fancy or important, but they didn’t have the symbolism of imperial rule.

Why is this symbolism relevant? Well, when England split from the Catholic Church under Henry VIII, part of the legal justification that Thomas Cromwell put together for the Act in Restraint of Appeals was that:

“Where by divers sundry old authentic histories and chronicles it is manifestly declared and expressed that this realm of England is an empire, and so hath been accepted in the world, governed by one supreme head and king, having the dignity and royal estate of the imperial crown of the same.”

Now, keep in mind that some of these “divers sundry old authentic histories” counted Brutus of Troy and King Arthur as examples of British imperial dignity, but Cromwell could point to Henry IV and Henry V, who both were crowned with an imperial crown (probably as an attempt to shore up their authority given the whole business with Richard II), as proof that England had previously claimed independence from the Pope in Rome.

How often would a medieval monarch wear his/her crown? – RSAFan

Not that often. Not only were full crowns rather heavy, they were often the most valuable thing the monarch owned, partly for the symbolic value the particular crown had but mostly because of all of the jewels and precious metals. Thus, wearing it from day to day would have been a huge risk. (Also, depending on the state of the royal finances, you might have had to pawn them…) So most of the time, the crown stayed in the vaults with the rest of the royal jewels and plate.

A further complication is that monarchs seldom had just the one crown. To use the English monarch as one example: St Edward’s Crown was the oldest of the Crown Jewels and goes back all the way to Edward the Confessor (hence the name), although parts of it supposedly go back to Alfred the Great. This crown represented stability and legitimacy of succession, as it had been used for every king pretty much between William the Conqueror and Charles I, so using it was very important: hence why Henry VIII used it to crown Anne Boleyn, a very public statement about the way things went. Incidentally, Parliament sold the crown in 1642 during the Civil War, and no one knows where the original went. (Charles II had a replacement made, and then Colonel Thomas Blood stole that one, and so on…)

Needless to say, you wouldn’t dream of using this crown except for coronations, so kings acquired other crowns to be used on different occasions. (Edward III, for example, had no less than nine crowns and a dozen circlets, because if you’re going to try to conquer France, you need to do that in style.) So when would a king wear a crown? Well, any major public event – a religious holiday, the installment of a bishop or the dedication of a church, a session of Parliament, meeting another monarch, making a pilgrimage, etc. etc.

For ordinary fancy occasions – your state dinners, your feasts, your dances, your earlier monarchs went with circlets or coronets. But fashions change, and once we get into the later Middle Ages, you start to see more of a preference for fancy hats as day-to-day wear. My personal favorite is Henry IV’s rather snazzy red number:

Now that is a hat that screams “I may be a usurper whose actions will lead to the Wars of the Roses, but you have to admit, I look damn good.”