"Anna" vs. "Annie"
This information comes mostly from Orrin Moen, Anna's nephew. I am just beginning to do some independent verification and refinement of my own. First off, all the Larson's spell her first name "Anna," but in Orrin's work, and presumably by all the Moen's, she is referred to as "Annie." The tree below shows four generations of her ancestors. Below the chart is a brief summary of Orrin's work tracing her lineage back more than 65 generations(!!!), to the Emperor Charlemagne and several centuries beyond. Way to go, Orrin!
Way, Way Back
In his work, begun long before so much information was available on the Internet, Orrin was diligently tracing our ancestors using paper sources and microfilms, notably the vast resources of the LDS (Mormon) Family History Centers. At some point, he hit on a strain of nobility/royalty, which in genealogical terms is like hitting the "mother lode," because the nobility a) keep meticulous records of their pedigrees, and b) are mostly related to each other.
Twenty generations before Anna (her "18th great grandmother" in the jargon) was Agnes Håkonsdatter (1275-1319), the illegitimate child of Håkon V Magnussen (1270-1319), King of Norway from 1299-1319. Now we are on Easy Street. There are even Wikipedia articles on these guys, and their relations. Here is the link for Håkon V.
According to Wikipedia, Håkon V was descended on his mother's side from St. Olaf himself. But Håkon V's paternal grandfather was nearly as legendary. As a two-year-old prince (the illegitimate son of Håkon III), his succession to the throne was violently challenged by the potent Bagler party, who favored another pretender. As the superior forces of the opposing military closed in, in the year 1206, the toddler prince was rescued by his loyal party, the Birkebeiner, in a daring winter run from Gudbrandsdal to Trondheim. He eventually succeeded as the powerful Håkon IV Håkonsen, AKA "Håkon the Old," and the Birkebeiner became an international Nordic ski racing event.
And going back from Håkon III, a partial list includes St. Vladimir I of Kiev (c. 958-1015), sainted for bringing Christianity to Russia, and Charlegmagne (742-814). Charlemagne himself was a big genealogy nut, and traced his own ancestry as far back as Richemer, King of the Franks (d. 114 AD) and beyond. Now that's some serious ancestors.
But Wait ...
As a matter of perspective, think of this: Charlemagne was my (and my siblings' and Larson first cousins') "35th great-grandfather." So, how many 35th great-grandfathers does a person, any person, have? Brace yourself: 68,719,476,736. Huh? That's right, mathematically, 68 billion. But, but ... by modern scientific estimate, the population of the entire world back then was around 250 million, less than 0.5% of that number. Check the blog for further explanation and comments.