The King Arthur Companion[1] is an Arthurian encyclopedia, written by Phyllis Ann Karr, with art by Jody Lee, edited and assembled by Chaosium, and published by Reston Publishing in 1983.

Subsequent editions expanded the contents, with the name changing in 2001 to The Arthurian Companion.

In 2017, a new edition, renamed The Arthurian Concordance was funded as part of a crowdfunding campaign.

[2] Originating in the research for Greg Stafford's 1979 board game King Arthur's Knights,[3] it eventually saw publication as a separate book in 1983 as an 8.5”x11” hardback with 174 pages.

[9] J. Michael Caporula reviewed the Chaosium release of The King Arthur Companion in Space Gamer/Fantasy Gamer No.