Hardy Hibiscus cultivar. Judging by the leaves, I would say Hibiscus coccineus was at leave one of the ancestors.

@Horntoad Yes the leaves caught my eye right away as coccineus, but that comes in only white and red; so seeing a pinkish lavender color with those leaves and dark eye truly stands out!

Although Hardy Hibiscus is often listed as Hibiscus moscheutos, in reality, they are crosses between some or all of the five native marsh Hibiscus.
The leaves on yours show H. coccineus characteristics. But the flower looks like a blend of H. cocineus and H. moscheutos, which can be either white or varying shades of pink, usually with red-eye. The shape of the flower looks like that of a wild H. moscheutos.

Is this an official cultivar, or a random result of cross breeding? It was given to me but I don't know it's history.

It's not one that I have ever seen, but there are so many I couldn't say for sure.

Horntoad ......Can you please put some names on the five native marsh Hibiscus.

Hibiscus coccineus, H. daisycalyx, H. grandiflorus, H. laevis and H. moscheutos. Hibiscus moscheutos has two subspecies. Subspecies moscheutos and subspecies laisiocarpos. Here's an article I wrote a few years ago. https://garden.org/ideas/view/...

The mystery of parentage might be close to solved, the seeds are fuzzy from this! @Horntoad

@Horntoad

I'm fairly sure Hibiscus laevis has fuzzy seeds, but I'm not 100% certain. The others I have no idea. I have photos at one time but lost a lot with computer problems. I still think H. coccineus is one of the parents as far as the rest is concerned, I couldn't really say. It could be carrying genes from just two or several species. Either way, it's a very nice looking plant.