The Schemes of Renly Baratheon

When we meet him in A Game of Thrones, he is a member of Robert's small council (a flatterer or a fool?) as the Master of Laws. I thought it would be fun to look at some of the schemes that he was up to before he crowned himself.

Background

As Renly is much younger (born in 277AC) than both Robert (262AC) and Stannis (264 AC), we don't have much info on his life after his childhood. He obviously grew up at Storm's End (pissing off Stannis who was given Dragonstone) at t

We know that he went on a Lord's Progression of the Stormlands once he turned 16:

That is a lie." Renly Baratheon had been more than a king to her. She had loved him since first he came to Tarth on his leisurely lord's progress, to mark his coming of age. Her father welcomed him with a feast and commanded her to attend; elsewise she would have hidden in her room like some wounded beast. ...

And Renly Baratheon had shown her every courtesy, as if she were a proper maid, and pretty. He even danced with her, and in his arms she'd felt graceful, and her feet had floated across the floor. Later others begged a dance of her, because of his example. -AFFC, Brienne I

and that once he became lord (unless he was knighted beforehand) he took Loras (born 282) as his squire at some point:

Someone will, but it will not be you. "Pray, who did you squire for, ser?" she asked sweetly. "Lord Renly, was it not?"

"I had that honor."

"Yes, I thought as much." Cersei had seen how tight the bonds grew between squires and the knights they served. She did not want Tommen growing close to Loras Tyrell.

We also know that he visited Sunspear when Arianne was still "half" a girl (Arianne is currently ~24 and would be two years older than Renly here):

Arianne had accepted that as well. One year King Robert's brother came to visit and she did her best to seduce him, but she was half a girl and Lord Renly seemed more bemused than inflamed by her overtures. Later, when Hoster Tully asked her to come to Riverrun and meet his heir, she lit candles to the Maid in thanks, but Prince Doran had declined the invitation. The princess might even have considered Willas Tyrell, crippled leg and all, but her father refused to send her to Highgarden to meet him. She tried to go despite him, with Tyene's help . . . but Prince Oberyn caught them at Vaith and brought them back. -AFFC, The Princess in the Tower

I think its just interesting that an early/mid teen Renly was in Dorne due to the political climate:

"No one speaks of it, but yes. Ravens flew and riders rode, with what secret messages I never knew. Jon Arryn sailed to Sunspear to return Prince Lewyn's bones, sat down with Prince Doran, and ended all the talk of war. But Robert never went to Dorne thereafter, and Prince Oberyn seldom left it." -ASOS, Tyrion VI

and while its pretty much an open secret among nobles, Oberyn is aware of Loras/Renly's relationship:

"There are those who say Ser Loras is better than Leo Longthorn ever was," said Tyrion.

"Renly's little rose? I doubt that." -ASOS, Tyrion V

If interested: Oberyn Martell's Whereabouts

At some point he is named Master of Laws and it should be noted that there is no love between the Lannisters and Renly:

"We ought to count ourselves fortunate," the man said. "The king might as easily have named one of his brothers, or even Littlefinger, gods help us. Give me honorable enemies rather than ambitious ones, and I'll sleep more easily by night.

and:

There is small love lost between Lord Renly and the Lannisters. -AGOT, Eddard XIII

Plotting to have Robert set aside Cersei and marry Margaery

In the ~year leading up to the series Renly and Loras are plotting pretty heavily to replace Cersei w/Maergary:

"He betrayed one already, or have you forgotten?" the woman said. "Oh, I don't deny he's loyal to Robert, that's obvious. What happens when Robert dies and Joff takes the throne? And the sooner that comes to pass, the safer we'll all be. My husband grows more restless every day. Having Stark beside him will only make him worse. He's still in love with the sister, the insipid little dead sixteen-year-old. How long till he decides to put me aside for some new Lyanna?" -AGOT Bran III

and:

The Knight of Flowers writes Highgarden, urging his lord father to send his sister to court. The girl is a maid of fourteen, sweet and beautiful and tractable, and Lord Renly and Ser Loras intend that Robert should bed her, wed her, and make a new queen. -AGOT, Arya III

andJ:

Ned was not sure what to make of Renly, with all his friendly ways and easy smiles. A few days past, he had taken Ned aside to show him an exquisite rose gold locklet. Inside was a miniature painted in the vivid Myrish style, of a lovely young girl with doe's eyes and a cascade of soft brown hair. Renly had seemed anxious to know if the girl reminded him of anyone, and when Ned had no answer but a shrug, he had seemed disappointed. The maid was Loras Tyrell's sister Margaery, he'd confessed, but there were those who said she looked like Lyanna. "No," Ned had told him, bemused. Could it be that Lord Renly, who looked so like a young Robert, had conceived a passion for a girl he fancied to be a young Lyanna? That struck him as more than passing queer. -AGOT, Eddard VI

and:

You never could lie for love nor honor, Ned Stark. I'm still young, and now that you're here with me, things will be different. We'll make this a reign to sing of, and damn the Lannisters to seven hells. I smell bacon. Who do you think our champion will be today? Have you seen Mace Tyrell's boy? The Knight of Flowers, they call him. Now there's a son any man would be proud to own to. Last tourney, he dumped the Kingslayer on his golden rump, you ought to have seen the look on Cersei's face. I laughed till my sides hurt. Renly says he has this sister, a maid of fourteen, lovely as a dawn …" -AGOT, Eddard VII

and:

"He was a wretched king . . . vain, drunken, lecherous . . . he would have set your sister aside, his own queen . . . please . . . Renly was plotting to bring the Highgarden maid to court, to entice his brother . . . it is the gods' own truth . . ." -ACOK, Tyrion VI

and:

"We both know your wedding was a mummer's farce. A year ago you were scheming to make the girl one of Robert's whores."

"A year ago I was scheming to make the girl Robert's queen," Renly said, "but what does it matter? -ACOK, Catelyn III

Plot to Keep take control of Joffrey+Tommen+Myrcella

As Robert is dying, Renly wants Ned to take control of the king:

Lord Renly glanced warily at Ser Boros on the far end of the span, at Ser Preston in the doorway behind them. "That letter." He leaned close. "Was it the regency? Has my brother named you Protector?" He did not wait for a reply. "My lord, I have thirty men in my personal guard, and other friends beside, knights and lords. Give me an hour, and I can put a hundred swords in your hand."

and:

"We must get Joffrey away from his mother and take him in hand. Protector or no, the man who holds the king holds the kingdom. We should seize Myrcella and Tommen as well. Once we have her children, Cersei will not dare oppose us. The council will confirm you as Lord Protector and make Joffrey your ward." -AGOT, Eddard XIII

and since Ned declines Renly's plan, Renly decides to flee instead:

Varys gave him a sorrowful look. "I fear Lord Renly has left the city."

"Left the city?" Ned had counted on Renly's support.

"He took his leave through a postern gate an hour before dawn, accompanied by Ser Loras Tyrell and some fifty retainers," Varys told them. "When last seen, they were galloping south in some haste, no doubt bound for Storm's End or Highgarden." -AGOT, Eddard XIV

TLDR: While we don't get much info on early Renly (minute chance he may have encountered Oberyn in Dorne), Renly does definitely start scheming while he is in King's Landing, but it does seem that while he is ambitious naming himself king was almost a last resort.