The post-apocalyptic Australia of George Miller's Mad Max franchise has always suffered from continuity problems. We don't know much about what happened to ruin the world, we don't understand the timeline, and when the actors get replaced after so many years, it's hard to keep up. But we didn't care as long as the movies were exciting. A new character in the upcoming film Furiosa: A Mad Max Saga may address that continuity in some form.
Furiosa: A Mad Max Saga is set before Mad Max: Fury Road, and will not involve the character Mad Max at all. Furiosa is played by Anya Taylor-Joy in the years before she becomes Charlize Theron. The narrator of the movie is known as History Man. He's also an important character. It appears that he is one of a group of History Men (and Women) who are tasked with keeping track of history as well as ongoing events after all the books were burned. Joe George at Den of Geek posits that the character, who briefly appeared in the 2015 Fury Road prequel comics, is an attempt to give the audience a sense of a timeline in the Mad Max world. We won't know how this will play out until Furiosa hits theaters on May 24th, or who knows- maybe not until future movies with the History Man.