1 cup (2 sticks) unsalted butter, room temperature, plus more for pans
3 cups all-purpose flour
2 teaspoons baking soda
1 teaspoon baking powder
1/2 teaspoon ground cinnamon
1/4 teaspoon ground allspice
1 pinch freshly grated nutmeg
1 teaspoon salt
1 pound (about 3 cups) dried figs, stemmed and chopped into 1/2 -inch pieces
1 3/4 cup packed light-brown sugar
4 large eggs
1 cup sour cream
1 cup (about 3 ounces) walnuts, toasted and coarsely chopped
Preheat the oven to 325 degrees Fahrenheit. Coat two 9-by-5-inch loaf pans with butter; set aside. In a large bowl, whisk together the flour, baking soda, baking powder, cinnamon, allspice, nutmeg, and salt; set mixture aside.
Bring 1 cup water to a simmer in a medium saucepan. Remove from heat, and add 1 1/2 cups dried figs; let stand until softened, about 10 minutes. Transfer figs and liquid to a food processor. Puree until smooth, about 1 minute; set aside.
In the bowl of an electric mixer fitted with the paddle attachment, beat the butter and brown sugar on medium-high speed until light and fluffy, 2 to 3 minutes. Add the eggs, one at a time, and mix to combine, scraping down the sides of the bowl as needed. Add the flour mixture, and beat until combined, 1 to 2 minutes. Add the sour cream and reserved fig puree; beat until just incorporated, about 1 minute. Using a rubber spatula, stir in the remaining chopped figs and the walnuts.
Divide the batter between the prepared pans; smooth the tops with an offset spatula. Place pans on a baking sheet. Bake, rotating the sheet halfway through, until deep golden brown and a cake tester inserted in the centers comes out clean, about 1 hour. Transfer the pans to a wire rack to cool 10 minutes. Remove loaves from pans and cool completely. Bread can be kept at room temperature, wrapped well in plastic, for up to 4 days.