Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
To add History Channel: On your computer go to Roky Channel Store. At top selection bar, arrow right until can select MOVIES & TV. Select and type HISTORY in the Search Bar and will locate History channel and all other tv channels available on Roku.
Both Philo (20$/mth) and Sling (25$/mth or more) offer History channel "live" as well as limited episodes from previous seasons - as long as you don't mind paying to watch a significant number of commercials (~20 min of ads per hour of viewing time), plus sharing your viewing habits with a variety of unknown "partners" of those providers.
If you want to go that route, watch for specials or introductory prices for the channels, as they occasionally offer deals for a few dollars off the monthly charges.