Soak yeast in 1/2 cup lukewarm water and leave for 5 minutes.
Make "sponge." Stir in 1 pint of lukewarm water, caraway seeds, salt and 4 cups of rye flour.
Leave in a warm spot for 1 1/2 hours, covered.
Stir in oil and 2 more cups rye flour.
Knead until smooth.
Place in oiled bowl and let rise in a warm spot, covered, for about 2 1/4 hours, until double in bulk.
Knead dough down, shape into round, high loaves (making 1 large or 2 smaller loaves), place on an oiled cookie sheet, cover and let rise in a warm spot for about 4 hours.
Meanwhile preheat oven to 350°F.
Bake in preheated oven for about one hour or until done.
Place a pan of hot water in the bottom of the oven to provide moisture during baking.
Brush loaf with oil when loaf is removed from oven.
Cool.