I’m not sure you already had this question but why did Renly choose to marry Margaery to Robert and not Joffrey? Wouldn’t he get the same advantages without the trouble of removing Cersei?

The point was to remove Cersei.

Cersei was a clear enemy of both Baratheon brothers (and vice versa), as we see from Bran II of AGOT where she talks to Jaime about all her enemies, or from Eddard XIII where Renly urges Ned to launch a coup against her, or from Sansa V of AGOT where Cersei marks down Renly as a traitor well before he declares his candidacy for the Iron Throne.

I’m sure I’ve missed it when I read the books, but why does Renly want to wed Margaery Tyrell to Robert?

Renly wants to wed Margaery Tyrell to Robert as part of a larger plan to oust the Lannisters – get Cersei out as queen, get Joffrey/Tommen/Myrcella out as heirs – and replace them with the Tyrells, with Renly likely becoming the next Hand of the King as the king’s loyal brother, the man responsible for uncovering Lannister treachery, and as a close ally of the Tyrells through Loras.

Is there a difference between “Your Grace” and “Your Majesty” in terms of deference and respect? Why is pre-conquest Westeros so uniform when it comes to royal styles?

Yes, and it has to do with fashions of royal address. According to Francois Velde of heraldica.org, “Your Highness” was the most common style across Europe from the 12th through 15th centuries CE. When Charles V became Holy Roman Emperor in 1519, he decided that he was too special to be a mere “Highness” – he did after all rule an empire that spanned from Asia to the Americas to eastern Europe – and instructed his court that he be described as “Majesty.”

Francois I of France, who would spend his entire reign fighting Charles V, wasn’t going to take this lying down and so insisted on also being referred to as “Majesty,” which led to a good deal of linguistic one-upmanship where Charles insisted on being called “Imperial Majesty” to Francois’ mere “Royal Majesty” and then Francois retaliated by using “Most Christian Majesty,” and so on. Henry VIII of England, who would be out-ego’d by no man, also began using “Majesty.” Just to confuse everyone, though, the English court continued to call him “Grace” and “Highness” as well as “Majesty” in legal documents, until the reign of James I, where it was regularized that the King is a “Majesty,” and Dukes and Archbishops are “Graces.”

So the TLDR is: a Majesty outranks a Grace.

To answer your second question, this is because GRRM wanted to simplify terms of address, the same reason that he used the same title of “lord” for everyone.

Do you think that the Others deliberately times their return at the worst possible moment? I feel that even without dragons a united Westeros would have been able to deal with the Others. Valyria before its doom had 300 dragons the sic on the Rhoynar, and presumably more on the homeland, before they all died. The Free Cities could have also provided help, and I think that they were built after the first Long Night. It feels that petty infighting is what makes the coming winter so dire.

I don’t think the Others have enough of a grasp on the human condition to make that kind of plan.

Rather, the timing has everything to do with GRRM’s love of dramatic irony and his desired levels of tension. If there were dozens of Targaryen dragons in the skies and the realm was united, then it wouldn’t be a very exciting story, would it?

I think for a north putting together an economic development plan, a western fleet like you proposed is crucial. On the other hand, a fleet just sitting around doing nothing during peace loses money and there’s not much trade opportunities for a northern merchant fleet since westerner and reacher merchants are better positioned. So, trying to circumnavigate the planet is a must for any northern economic development plan in my opinion. It’s either the riches of the east or an unspoiled continent.

I don’t agree that “there’s not much trade opportunities for a northern merchant fleet.” If there’s enough trade opportunities for the hardscrabble Iron Islands to have an active port town doing business from southern Westeros and Essos both:

“The Myraham was a fat-bellied southron merchanter up from Oldtown, carrying wine and cloth and seed to trade for iron ore…A handful of Lordsport merchants had gathered to meet the ship. They shouted questions as the Myraham was tying up. “We’re out of Oldtown,” the captain called down, “bearing apples and oranges, wines from the Arbor, feathers from the Summer Isles. I have pepper, woven leathers, a bolt of Myrish lace, mirrors for milady, a pair of Oldtown woodharps sweet as any you ever heard…”

“…Theon was more interested in ships than gods. Among the masts of countless fishing boats, he spied a Tyroshi trading galley off-loading beside a lumbering Ibbenese cog with her black-tarred hull.”

“…She had surrendered her virtue at six-and-ten, to a beautiful blond-haired sailor on a trading galley up from Lys.”

then there’s no reason that the vast agricultural markets of the North just on the other side of the Flint Cliffs from Ironman’s Bay, wouldn’t find buyers from among the ships that sail the northern stretches of the Sunset Sea.

By contrast, trying to sail west across the Sunset Sea has historically been a fool’s venture:

“Strange tales like this are common at the edges of the world, however, and the Lonely Light stands farthest west of all the lands known to us. Many a bold mariner has sailed beyond the light of its beacon over the centuries, seeking the fabled paradise said to lie over the horizon, but the sailors who return (many do not) speak only of boundless grey oceans stretching on and on forever.”

Was the idea of a regency for Aegon VI and Rhaenys ever really explored by the rebel faction? Rhaegar may have been more agreeable to a surrender if he knew his children would succeed him, and it was possible for him to take the black. Or did Robert just really want the throne that badly?

No, the idea was not explored, because the Rebel Alliance acclaimed Robert as their king – note the order of operations there – and once you’ve crossed that particular Rubicon, there is no alternative to removing House Targaryen altogether.

And I should emphasize, because I’ve responded to a few of these, but the political logics of a lot of these alternate scenarios are not sound. Even if Rhaegar was willing to take the black (unlikely), and Rhaegar’s supporters would accept that (unlikely), it’s not a good idea for the Rebel Alliance to support a regency for Aegon VI, because infant kings grow up and have excellent motives to revenge themselves against the people who overthrew their fathers.

Why is the North’s western shore so poorly defended against Ironborne? Seagard has its belltower and the Reach has watchtowers and the Shield Islands, but none such structures are ever mentioned for the North.

A couple reasons:

The North’s population is more interior than coastal, so the shore is less important than it is in the Westerlands or the Riverlands or the Reach.
The North had better defenses at various times – “Balon V Greyjoy,
called Coldwind, destroyed the feeble fleets of the King in the North…We have had no strength at sea for hundreds of years, since Brandon the Burner put the torch to his father’s ships” – but have neglected them in recent centuries.
Even without those defenses, the Ironborn don’t do well trying to hold the North, in part because “ironborn lack the discipline to stand a charge of armored horse.”

Did Robb plan to incorporate the Golden Tooth into his new realm?

Unlikely. Robb’s offer of peace describes his kingdom as incorporating:

“…all the Stark lands north of the Neck, and in addition the lands watered by the River Trident and its vassal streams, bounded by the Golden Tooth to the west and the Mountains of the Moon in the east.“

If Robb had seized the Golden Tooth in battle, it might have been a different story, but it doesn’t seem like he was making any claim on that particular castle.

If the Tyrell’s managed to get Sansa out of KL before she got married off to Tyrion – and was married off to Wilas in Highgarden – would their son have been lord paramount of both the North and The Reach? How come two great houses had never had an heir like thst in 300 years?

1. Yes, although more likely they would have split the titles between first and second sons.

2. Because there’s a cultural taboo against combining land holdings – “Holdings are seldom divided. Nor are they combined, as a rule, although one person could concievably hold more than one title.” – which makes sense from a geopolitical perspective. It’s hard to administer two far-flung holdings, and there would be a good deal of tension about favoritism, where the heir will be raised so they’re not considered a “foreigner,” etc.

Given that the Lannisters and the Tyrells were allies, why would the Lannisters object to Sansa marrying into House Tyrell? Could this be seen as an early sign that the supposed grand alliance was very much a marriage of convenience that both parties hoped to rid themselves of as soon as possible?

It was always a marriage of convenience. Tywin’s entire strategy hinges on giving them just as much as is needed to keep them on-side and hungry for more, without giving them too much and make them independent of the Lannisters.

The North is not only a huge asset in and of itself, but a marriage alliance between House Tyrell and House Stark possibly reorients the political cast of the war:

Bloody fool, thought Tyrion. “Sweet sister,” he explained patiently, “offend Tyrell and you offend Redwyne, Tarly, Rowan, and Hightower as well, and perhaps start them wondering whether Robb Stark might not be more accommodating of their desires.”

“I will not have the rose and the direwolf in bed together,” declared Lord Tywin. (ASOS Tyrion III)