Pour hot water over 1/4 cup raisins to cover by at least 1 inch. Soak for at least 10 minutes, or up to several hours. Drain.
Heat olive oil in a Dutch oven over medium heat. Add chopped red onions and saute until translucent, about 5-7 minutes. Stir in 2 cloves garlic (minced) and 1 teaspoon dried oregano and cook until fragrant, about 1 minute.
Stir in chopped eggplant and 1 1/2 pounds eggplant and cook until eggplant is softened, about 10 minutes. Add chopped tomatoes, chopped olives, 2 Tablespoons capers, and soaked raisins. Cook until heated through. Serve hot or at room temperature over rice or pasta, or with bread. Tastes even better the next day after flavors have melded.