Season the flour with salt and pepper and use to coat the venison. Crush the juniper berries using a pestle and mortar.
Heat the oil in a large, flameproof casserole and fry the meat in batches until browned, draining each batch to a plate. Add the bacon, onion and carrots to the casserole and fry gently for 5 minutes or until browned.
Stir in the crushed juniper berries, cloves, wine, stock, vinegar and redcurrant jelly and bring to the boil. Reduce the heat and stir in the chestnuts and venison.
Cover with a lid and place in a preheated oven, 160°C (325°F), Gas Mark 3, for 1 hour. Check the seasoning, then scatter with the potatoes and return to the oven, covered, for a further 30 minutes.
Blend the rosemary with the butter and a little seasoning and dot over the potatoes. Return to the oven, uncovered, for a further 45 minutes or until the potatoes are lightly browned.