Yes I thoroughly enjoyed Zack Snyder's '300' movie even though I didn't think I would. It was pretty spectacular. There has been talk of a sequel to the film but most people would think that there is no way because everyone pretty much died in the first film. Just so you know there are several stories that can be told that happen after the battle of Thermopylae. When Zack Snyder was asked if he would direct the sequel if the studio asked him to he said "Sure". He goes on to say:
“There’s something that happens in history between Leonidas dying at the Hot Gates and Platea, That’s a year that’s left out of the [original] movie. A lot happened.”
Yes a lot did happen. This sounds like it will be more of a different event that happened around the same time as what happened in the first movie. Now Snyder was very vague with his description of "a Lot" so let me break it down for you of what this movie will most likely be about.
It could be that Battle of Artemisium which took place the same day as the Battle of Thermopylae. This was a huge naval battle that took place on the sea near Thermopylae and involved an alliance of Greek city-states fighting against the Persians. When The Greek learned of Leonidas’ defeat at Thermopylae they retreated.
The Persians recovered Leonidas’ body and Xerxes had his head cut off and his body crucified.
Then there was the Battle of Salamis, this was another naval battle in which the Greeks defeated the Persians. Then the remaining Persian army was taken out at the Battle of Plataea by a Greek Army once again led by the Spartans. This was the final major battle of the Greco-Persian Wars. This time Sparta sent 10,000 men instead of 300. With all Greek army’s combined they had 110,000 men.
I assume it will end up being one of these massive naval battles, but you never know. Snyder goes on to say:
“Frank is definitely working on an idea. If Frank comes up with a great idea and draws something cool, there’s no reason why we wouldn’t make another movie.”
So there ya have it folks. It's all on Frank Millers shoulders now. If he does it then we will see a new Spartan movie, if not then we won't. Personally I hope it happens. What do you want to see come out of this if anything?