Sprinkle chicken with 1-1/2 tsp. rosemary, salt and pepper. Heat oil in heavy medium skillet over medium heat.
Add chicken to skillet; sauté until brown and just cooked through, about 5 minutes per side. Using tongs, transfer chicken to plate. Increase heat to medium-high.
Add peppers to same skillet; sauté until wilted and beginning to brown, about 3 minutes. Add garlic and remaining 1 1/2 tsp. rosemary; stir until fragrant, about 30 seconds. Mix in olives and vinegar.
Return chicken and any accumulated juices on plate to skillet. Simmer until chicken is heated through, about 2 minutes.
Season with salt and pepper. Transfer chicken to plates. Spoon pepper mixture over and serve.
