A livestream presentation announced on Saturday that the new anime film adaptation of Hideaki Sorachi's Gintama manga will open in Japan in 2021. The manga's 77th and final compiled book volume announced the film on August 2.
Sorachi's original manga, which began in 2004 and ended in June, has inspired seven television anime series and 367 total episodes. The latest series premiered in July 2018.
Hulu began streaming the first 49 episodes with an English dub on December 1. The only previous episodes to receive an English dub are episodes 266 through 316 (considered season 3 of the anime). Those episodes are available to stream on Crunchyroll and Funimation, and the companies released them on home video in 2018.
Sentai Filmworks released the anime's first 49 episodes on DVD in 2010 and 2011. That release did not include an English dub.
The manga has also inspired two other anime films, various OVAs and event anime, two live-action films, and two live-action net spinoff series. Viz Media published the manga's first 23 volumes in English.
Source: Jump Festa 2020 Anime Gekijōban Gintama ~Boku-tachi no Super Stage~ livestream