Combine Italian seasoning, salt and pepper in a small bowl. Mix this seasoning rub over the surface of the roast. Heat olive oil in a large nonstick or cast-iron skillet over medium-high heat. Add pieces of roast; cook 8 minutes, browning all sides to get a good sear. Remove roast from pan; place in a 3 to 4 quart electric slow cooker. Add onion and garlic to pan that the roast seared in. Place over medium heat, and saute for 5 minutes. Add broth, scraping pan to loosen browned bits. Pour mixture over roast in cooker.

Arrange potatoes and olives around roast, sprinkle with capers and dried oregano. Cover and cook on LOW for 9 hours. Add artichoke hearts and cook an additional hour. Place roast on a large platter. Arrange vegetables, olives and cpaers around the roast. Garnish with fresh oregano sprigs, if desired.