Heraldry, of which a coat of arms is a part, has a very deep, rich history associated with it. If you've studied heraldry at all, you may be somewhat confused by the colors and symbols I've chosen below (what's up with the Kingdom of Mejasta?).
For those of you who have no idea what I'm talking about, colors and symbols chosen for a coat of arms represent various characteristics of the person, family, or organization the coat of arms represents. For instance, the color (or "tincture") blue (aka "azure") is associated with truth and loyalty; that works out well for the Kingdoms of Mareten and the Elves, the Church, and the Wall Guards; however, green (aka "vert") means "Hope, joy, and loyalty in love," which sounds great, but doesn't belong with the Assassin's Guild. Or any of the Zaharan cities, for that matter. Symbols matter, too; crossed keys (such as on the Thieves' Guild arms) is the symbol of St. Peter, and represent the keys to the gates of heaven. The lion, like on the Kingdom of Mareten's coat of arms, means courage, which works well enough. The sythe on the Assassin's Guild coat of arms usually means hope, as in hope of a good harvest; again, not particularly fitting. Then again, not all heraldry was entirely truthful; when it came down to it, I'm sure a great number of coats of arms had little to do with the actions of their bearer...
However, for your enlightenment and my pleasure, I've added a key at the bottom of this page, to explain the meanings of the various colors and images. Please note that these are not the historical meanings from our world, but from the world of Mor-Thir.
From kingdom to peasant family, every organization has a crest. Here are a few that I've come up with:
(also a symbol of Thor)
(also a symbol of various chaotic deities)