With The Lord of the Rings: The War of the Rohirrim upon us, fans have already begun speculating. As the newest addition to the Lord of the Rings franchise is going to be an anime movie, directed by Kenji Kamiyama, we know we cannot expect any of our favorite actors to make an appearance, but this is not to say that fans don't wonder if they are going to see animated reimaginings of favorite characters. So, will Gandalf, or any other characters from the original book and film trilogy make it to The War of the Rohirrim?
At the moment, we don't have a trailer or full plot details about the Lord of the Rings anime, but what we do know, suggests that while the new film is canon, characters we know and love are unlikely to appear. This is because The War of the Rohirrim will take place 250 years prior to the events of The Lord of the Rings.
In fact, the anime movie will be based on details found in the appendixes at the end of The Lord of the Rings book. It is most likely going to tell the story of Helm Hammerhand, a legendary king of Rohan, and his war with the Dunlendings, a rival tribe of men. We expect Helm's story to be a sad one, as he's the last of his line. During the war of the Rohirrim, both his sons die, and he's succeeded by his sister's son, Fréaláf.
Given that this story unfolds so long before the events of The Lord of the Rings, we know we can't expect any of the hobbits or humans we know to appear in The War of the Rohirrim as none of the characters from these races that appear in LotR were born at the time. Others, including Gandalf, as well as elves, such as Elrond and Legolas, were already alive. This does not mean that they are going to appear in the anime movie, of course; these characters aren't known to have been involved in that particular conflict.
Of course, The War of the Rohirrim is going to be an adaptation, so the writers could theoretically make the choice to use some of the characters we know and love, as long as they can safely do so without disputing the canon. It is unlikely, but we have to wait for the movie to come out to make sure.