diff --git a/docs/metadata/data_structures/message.rst b/docs/metadata/data_structures/message.rst
index 3103e189..3d4e86c6 100644
--- a/docs/metadata/data_structures/message.rst
+++ b/docs/metadata/data_structures/message.rst
@@ -44,7 +44,21 @@ Messages are given as key-value maps.
 Language Support
 ----------------
 
-If a message's ``content`` value is a string, the message will use the string as its content if displayed. Otherwise, the first localised content structure with a language that matches LOOT's current language will be used as the message's content if displayed. If there are no matches, then the first structure in English will be used.
+If a message's ``content`` value is a string, the message will use the string as
+its content if displayed. Otherwise, the first localised content structure with
+a language or locale code that matches LOOT's current language will be used as
+the message's content if displayed. If there are no exact matches, LOOT will try
+to find a close match. If LOOT's current language uses a locale code, it will
+display the first structure with the same language code, but not another locale
+code with the same language code. For example, if LOOT's current language has
+locale code ``pt_BR``, it will display the first structure with language code
+``pt`` (but not locale code ``pt_PT``) if none exist with locale code ``pt_BR``.
+If LOOT's current language has a language code, it will display the first
+structure with a locale code that contains that language code. For example, if
+LOOT's current language has language code ``pt``, it will display the first
+structure with locale code ``pt_PT`` or ``pt_BR`` if none exist with language
+code ``pt``. If there are no exact or close matches, then the first structure in
+English will be used.
 
 Equality
 --------