Put the potatoes in the insert of a 5- to 7-quart slow cooker. Cook the bacon in a large skillet over medium heat until crisp and remove it to paper towels to drain, leaving the drippings in the pan.
Sprinkle the chicken evenly with 1-1/2 teaspoons salt and 1/2 teaspoon pepper and add to the bacon drippings.
Brown the chicken on all sides, 12 to 15 minutes. Remove the chicken to the slow cooker. Add the rosemary and garlic to the pan drippings and sautÃ© for 1 to 2 minutes. Deglaze the skillet with the vinegar, scraping any browned bits from the bottom, and transfer the contest of the skillet to the slow-cooker insert.
Add the broth. Cover and cook on high for 3 hours or on low for 5 to 6 hours, until the chicken and potatoes are tender. Season with salt and pepper.
Sprinkle the reserved bacon over the top of the chicken and potatoes before serving.