Actually, it sounds like alternate history but it's not:
"In 1815-17, Kaumuali'i led secret negotiations with representatives of the Russian-American Company in an attempt to gain Russia's military support against Kamehameha; however, the negotiations folded and the Russians were forced to abandon all of their presence in Kaua'i, including Fort Elizabeth, after it was revealed that they did not have the support of Tsar Alexander I."
More here - perhaps, even stranger to my American eyes and ears than the 17th century Swedish colony in Delaware. I would think some fascinating alternative history could be written about either of these, but like all fiction, alternative history is about us, here and now, and here and now we don't think much about the Russian and Swedish forays into Hawaii and Atlantic North America (although there's online discussion of Russian Hawai'i of course, here's an online crack at a surviving New Sweden...)
I only just discovered the Points of Divergence alternate history site, which I will surely be wandering around in the coming days.