2 files changed, 49 insertions, 0 deletions
diff --git a/src/SMAPI/Events/IContentEvents.cs b/src/SMAPI/Events/IContentEvents.cs
index abbaaf33..d537db70 100644
--- a/src/SMAPI/Events/IContentEvents.cs
+++ b/src/SMAPI/Events/IContentEvents.cs
@@ -19,5 +19,9 @@ namespace StardewModdingAPI.Events
         /// <summary>Raised after an asset is loaded by the content pipeline, after all mod edits specified via <see cref="AssetRequested"/> have been applied.</summary>
         /// <remarks>This event is only raised if something requested the asset from the content pipeline. Invalidating an asset from the content cache won't necessarily reload it automatically.</remarks>
         event EventHandler<AssetReadyEventArgs> AssetReady;
+
+        /// <summary>Raised after the game language changes.</summary>
+        /// <remarks>For non-English players, this may be raised during startup when the game switches to the previously selected language.</remarks>
+        event EventHandler<LocaleChangedEventArgs> LocaleChanged;
     }
 }
diff --git a/src/SMAPI/Events/LocaleChangedEventArgs.cs b/src/SMAPI/Events/LocaleChangedEventArgs.cs
new file mode 100644
index 00000000..09d3f6e5
--- /dev/null
+++ b/src/SMAPI/Events/LocaleChangedEventArgs.cs
@@ -0,0 +1,45 @@
+using System;
+using LanguageCode = StardewValley.LocalizedContentManager.LanguageCode;
+
+namespace StardewModdingAPI.Events
+{
+    /// <summary>Event arguments for an <see cref="IContentEvents.LocaleChanged"/> event.</summary>
+    public class LocaleChangedEventArgs : EventArgs
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The previous language enum value.</summary>
+        /// <remarks>For a custom language, this is always <see cref="LanguageCode.mod"/>.</remarks>
+        public LanguageCode OldLanguage { get; }
+
+        /// <summary>The previous locale code.</summary>
+        /// <remarks>This is the locale code as it appears in asset names, like <c>fr-FR</c> in <c>Maps/springobjects.fr-FR</c>. The locale code for English is an empty string.</remarks>
+        public string OldLocale { get; }
+
+        /// <summary>The new language enum value.</summary>
+        /// <remarks><inheritdoc cref="OldLanguage" select="remarks" /></remarks>
+        public LanguageCode NewLanguage { get; }
+
+        /// <summary>The new locale code.</summary>
+        /// <remarks><inheritdoc cref="OldLocale" select="remarks" /></remarks>
+        public string NewLocale { get; }
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="oldLanguage">The previous language enum value.</param>
+        /// <param name="oldLocale">The previous locale code.</param>
+        /// <param name="newLanguage">The new language enum value.</param>
+        /// <param name="newLocale">The new locale code.</param>
+        internal LocaleChangedEventArgs(LanguageCode oldLanguage, string oldLocale, LanguageCode newLanguage, string newLocale)
+        {
+            this.OldLanguage = oldLanguage;
+            this.OldLocale = oldLocale;
+            this.NewLanguage = newLanguage;
+            this.NewLocale = newLocale;
+        }
+    }
+}