Any idea on if the Summer Islanders will get involved in real world style mass slave trading, colonialism, or imperialism? The seem to have a serious naval advantage that would support such things.

Given the Summer Isles’ history, I’m going to say no:

“The Valyrians offered gold for slaves as well. Then as now, the Summer Islanders were a handsome people, tall, strong, graceful, and quick to learn. These qualities drew pirates and slavers from Valyria, the Basilisk Isles, and Old Ghis. Much woe ensued as these raiders descended on peaceful villages to carry their inhabitants into bondage. For a time, the princes of the isles abetted this trade by selling captured foes and rivals to the slavers.

The histories carved into the Talking Trees tell us that these “Years of Shame” endured for the better part of two centuries, until a warrior woman named Xanda Qo, Princess of Sweet Lotus Vale (who had herself been enslaved for a time), united all the islands under her rule and made an end to it.

Though it took the best part of a generation, the Summer Islanders, led by Princess Xanda’s daughter (and eventual successor) Chatana Qo, the Arrow of Jhahar, ultimately prevailed in what came to be known as the Slavers’ Wars. Though the unity of the isles did not survive her own reign (for the Arrow wed unwisely and did not rule as well as she had fought) slavers even now will flee at the sight of a swan ship, for each of these proud vessels is known to carry a complement of deadly archers armed with goldenheart bows.”

So antipathy towards slavery is a significant part of the Summer Islanders’ culture – carved deep into the Talking Trees they venerate. Likewise, “the Summer Islanders have never once invaded any lands beyond their own shores nor attempted the conquest of any foreign people.”