What does "whose shadows were all about her" modify in this text?

Question

I would like to know what "whose shadows were all about her" modifies in this sentences:

ON a hill by the Mississippi where Chippewas camped two generations ago, a girl stood in relief against the cornflower blue of Northern sky. She saw no Indians now; she saw flour-mills and the blinking windows of skyscrapers in Minneapolis and St. Paul. Nor was she thinking of squaws and portages, and the Yankee fur-traders whose shadows were all about her. She was meditating upon walnut fudge, the plays of Brieux, the reasons why heels run over, and the fact that the chemistry instructor had stared at the new coiffure which concealed her ears.

• Sinclair Lewis, Main Street, Chapter 1

Carol fled from her college for an hour and was standing on the hilltop, meditating upon walnut fudge and so on.

In this part, I could not be sure whether "whose shadows were all about her" modifies only "the Yankee fur-traders," or "squaws and portages and the Yankee fur-traders" altogether.

At first, I thought the former was the case, because the squaws and portages and the Yankee fur-traders were separated by a comma; but as I examined the text, squaws and portages also seemed to be capable of leaving shadows about her, so I became confused.

And about the expression "shadows," would it be alright to interpret it that the past existences left traces, or footprints, all about her, who was standing on the hilltop today?

I would very much appreciate your help. :)

Answer 1

Shadows is modifying only the Yankee fur-traders, as you first thought. The comma makes this clear. The sentence would have worked without it, so it's only there to make this division. As for your second question, as the paragraph dwells on the past, I think that's a very reasonable interpretation.