Sorry the link didn't come thru in my post up above. Here it is. http://www.quilthistory.com/repair.htm

After you talk to the insurance agent!, lay on lawn and rinse gently with the hose--to loosen and wash away the bulk of surface stuff. I would put these on a clean sheet and use the sheet to actually pick up the quilt from the lawn. Then use your bath tub and a plastic laundry basket using Retro CLean --follow the directions and you'll probably need to re-do a couple of times if badly soiled; put the quilt in the laundry basket (and the sheet you picked it up with if still wet) to swish the quilt up and down and lift from tub. Then lay out on that sheet again on flat surface--if on lawn be sure to put out of the sun so you don't get sun damage. Had a friend have similar disaster and this worked. But do contact insurance first.

I have found that Blue Dawn, peroxide and baking soda will take out any stains that I have encountered. I usually lightly dampen, put Blue dawn directly on it, spray peroxide and then sprinkle baking soda and then spray peroxide to make a paste and then lightly rub with a soft brush (I usually use an old toothbrush). Then wash in machine or in your case, rinse thoroughly. Since the material is so old, I would do an edge of whatever you use to do a test drive.
I pray that these heirloom quilts will be salvaged. If not, you might consider framing pieces.

I wouldn't put peroxide on fabric that is over a hundred years old.

Lady Diana has a very important point. Peroxide breaks down organic molecules. It's great for removing organic stains, such as pet mess, from non-organic fibers such as nylon carpet. The organic dyes that might be in the old quilts could easily be harmed by it. I think because of the significance of these quilts in your family it would be best to get professional advice from a museum. I'm so sorry for the trauma of having a fire in your home.