The movie was running in German free TV in the early 2000s but was most likely American. In the beginning people were stranding at a beach. They all had just died in different points in time, I think the protagonist was an astronaut, but there was also a Roman emporer (Nero I think) and one of his subordinates. In the group was also a mute child, which was the only child around. Everyone has a little metal stick which could be used to gather food at big futuristic distribution devices.
Some guy had built a castle over the last 10 years and became the ruler of the island. Another group, including an alien if I remember correctly, had build a ship and wanted to go somewhere. At that point I had to stop watching the movie and since then I wonder what happened. If someone could help me out, I’d be so grateful.