Founded: 1975 (Still ongoing)
This company published the first version of Adventures in Fantasy in 1978. After the initial run, the game reverted back to Dave Arneson and Richard Snider who then turned it over to Dave's company, Adventure Games.

Sources:
Wikipedia: No Wikipedia Page Found
Facebook: https://www.facebook.com/pg/ExcalibreGames/
Boardgame Geek: https://boardgamegeek.com/boardgamepubl ... -games-inc
Website: http://www.excalibregames.com/

-Havard