diff --git a/src/class.c b/src/class.c
index 07a045838..7b216a516 100644
--- a/src/class.c
+++ b/src/class.c
@@ -3077,10 +3077,6 @@ mrb_class_initialize(mrb_state *mrb, mrb_value obj)
 {
   struct RClass *c = mrb_class_ptr(obj);
 
-  if (c->iv) {
-    mrb_raise(mrb, E_TYPE_ERROR, "already initialized class");
-  }
-
   mrb_value a, b;
   mrb_get_args(mrb, "|C&", &a, &b);
   if (!mrb_nil_p(b)) {
@@ -3099,6 +3095,7 @@ mrb_class_new_class(mrb_state *mrb, mrb_value cv)
     super = mrb_obj_value(mrb->object_class);
   }
   mrb_value new_class = mrb_obj_value(mrb_class_new(mrb, mrb_class_ptr(super)));
+  mrb_class_inherited(mrb, mrb_class_ptr(super), mrb_class_ptr(new_class));
   mrb_sym mid = MRB_SYM(initialize);
   if (mrb_func_basic_p(mrb, new_class, mid, mrb_class_initialize)) {
     mrb_class_initialize(mrb, new_class);
@@ -3106,7 +3103,6 @@ mrb_class_new_class(mrb_state *mrb, mrb_value cv)
   else {
     mrb_funcall_with_block(mrb, new_class, mid, n, &super, blk);
   }
-  mrb_class_inherited(mrb, mrb_class_ptr(super), mrb_class_ptr(new_class));
   return new_class;
 }
 
diff --git a/test/t/class.rb b/test/t/class.rb
index 65eb5edd4..fcdb7a88b 100644
--- a/test/t/class.rb
+++ b/test/t/class.rb
@@ -503,3 +503,39 @@ assert('module with extended callback') do
   assert_true BarBeingExtended.respond_to?(:answer)
   assert_equal 42, BarBeingExtended.answer
 end
+
+assert("inherited hook runs before block body") do
+  class A
+    def self.values
+      @values ||= []
+    end
+
+    def self.inherited(mod)
+      mod.values << 1
+    end
+  end
+
+  klass = Class.new(A) do
+    self.values << 2
+  end
+
+  assert_equal [1, 2], klass.values
+end
+
+assert("inherited hook runs before class body") do
+  class A
+    def self.values
+      @values ||= []
+    end
+
+    def self.inherited(mod)
+      mod.values << 1
+    end
+  end
+
+  class B < A
+    self.values << 2
+  end
+
+  assert_equal [1, 2], B.values
+end