Rinse peas, and combine with remaining ingredients in slow cooker.
Give everything a quick stir, and then set slow cooker to HIGH and cook 4-6 hours. If possible, stir it about halfway through.
After cooking for 5-6 hours, the meat on the ham-bone should be falling apart. Reduce the slow cooker to LOW. If your soup seems too thick, add more water at this time.
Using tongs or an extra-large serving spoon, carefully remove ham bone to a plate to cool.When the ham bone is cool enough to handle, remove any ham and return the meat to the soup. Discard the ham bone.
Adjust seasonings to taste and serve.
Split pea soup thickens dramatically with time, and is best "the day after," when the flavors have melded, and the starches have had a chance to do their job as they naturally thicken the soup.