Peel and finely chop the garlic. Chop enough of the rosemary leaves to measure 1teaspoon.
Put the olive oil in a heavy-bottomed braising pan and place over high heat. When the oil is hot enough to make the lamb sizzle, put in half the meat and lightly brown it on all sides. Transfer to a platter and repeat with the remaining lamb. When all of the lamb is done, season the meat with salt and pepper.
Add the garlic and rosemary to the pan and lower the heat to medium-high. Add the wine and let it bubble for about 30 seconds to let the alcohol evaporate. Add the tomatoes and break them up with a wooden spoon. Lightly season the tomatoes with salt and, once they begin bubbling, return the meat to the pan. Adjust the heat so that the tomatoes simmer and cover with the lid slightly askew. Cook, stirring every 15 to 20 minutes, until the meat is tender, about 1½ hours. If all the liquid evaporates before the lamb is tender, add a little water.
While the meat is cooking, chop enough of the parsley leaves to measure 2tablespoons. Slice the flesh of the olives away from the pits.
When the meat is tender, add the parsley and olives and continue cooking for about 5 minutes. If there is a lot of liquid in the pan, raise the heat and finish cooking uncovered to let the excess liquid evaporate. Serve hot.
This dish can easily be made 1 to 2 days ahead of time and kept in the refrigerator. Wait to add the olives and parsley until you are ready to reheat the stew and serve it.