diff --git a/Library/Homebrew/locale.rb b/Library/Homebrew/locale.rb
index 40647ea62c..ac6b24c6a6 100644
--- a/Library/Homebrew/locale.rb
+++ b/Library/Homebrew/locale.rb
@@ -17,14 +17,14 @@ class Locale
   LANGUAGE_REGEX = /(?:[a-z]{2,3})/.freeze
   private_constant :LANGUAGE_REGEX
 
-  # ISO 3166-1 or UN M.49
-  REGION_REGEX = /(?:[A-Z]{2}|\d{3})/.freeze
-  private_constant :REGION_REGEX
-
   # ISO 15924
   SCRIPT_REGEX = /(?:[A-Z][a-z]{3})/.freeze
   private_constant :SCRIPT_REGEX
 
+  # ISO 3166-1 or UN M.49
+  REGION_REGEX = /(?:[A-Z]{2}|\d{3})/.freeze
+  private_constant :REGION_REGEX
+
   LOCALE_REGEX = /\A((?:#{LANGUAGE_REGEX}|#{REGION_REGEX}|#{SCRIPT_REGEX})(?:-|$)){1,3}\Z/.freeze
   private_constant :LOCALE_REGEX
 
@@ -56,18 +56,18 @@ class Locale
 
     return unless scanner.eos?
 
-    new(language, region, script)
+    new(language, script, region)
   end
 
-  attr_reader :language, :region, :script
+  attr_reader :language, :script, :region
 
-  def initialize(language, region, script)
+  def initialize(language, script, region)
     raise ArgumentError, "#{self.class} cannot be empty" if language.nil? && region.nil? && script.nil?
 
     {
       language: language,
-      region:   region,
       script:   script,
+      region:   region,
     }.each do |key, value|
       next if value.nil?
 
@@ -84,7 +84,7 @@ class Locale
       return false if other.nil?
     end
 
-    [:language, :region, :script].all? do |var|
+    [:language, :script, :region].all? do |var|
       if other.public_send(var).nil?
         true
       else
@@ -99,7 +99,7 @@ class Locale
       return false if other.nil?
     end
 
-    [:language, :region, :script].all? do |var|
+    [:language, :script, :region].all? do |var|
       public_send(var) == other.public_send(var)
     end
   end
@@ -112,6 +112,6 @@ class Locale
 
   sig { returns(String) }
   def to_s
-    [@language, @region, @script].compact.join("-")
+    [@language, @script, @region].compact.join("-")
   end
 end
diff --git a/Library/Homebrew/test/cask/dsl_spec.rb b/Library/Homebrew/test/cask/dsl_spec.rb
index 61eadc8fea..0289ce608a 100644
--- a/Library/Homebrew/test/cask/dsl_spec.rb
+++ b/Library/Homebrew/test/cask/dsl_spec.rb
@@ -165,7 +165,7 @@ describe Cask::DSL, :cask do
             "zh-CN"
           end
 
-          language "en-US", default: true do
+          language "en", default: true do
             sha256 "xyz789"
             "en-US"
           end
diff --git a/Library/Homebrew/test/locale_spec.rb b/Library/Homebrew/test/locale_spec.rb
index 3b627c7705..b20d275ced 100644
--- a/Library/Homebrew/test/locale_spec.rb
+++ b/Library/Homebrew/test/locale_spec.rb
@@ -7,13 +7,13 @@ describe Locale do
   describe "::parse" do
     it "parses a string in the correct format" do
       expect(described_class.parse("zh")).to eql(described_class.new("zh", nil, nil))
-      expect(described_class.parse("zh-CN")).to eql(described_class.new("zh", "CN", nil))
-      expect(described_class.parse("zh-Hans")).to eql(described_class.new("zh", nil, "Hans"))
-      expect(described_class.parse("zh-Hans-CN")).to eql(described_class.new("zh", "CN", "Hans"))
+      expect(described_class.parse("zh-CN")).to eql(described_class.new("zh", nil, "CN"))
+      expect(described_class.parse("zh-Hans")).to eql(described_class.new("zh", "Hans", nil))
+      expect(described_class.parse("zh-Hans-CN")).to eql(described_class.new("zh", "Hans", "CN"))
     end
 
     it "correctly parses a string with a UN M.49 region code" do
-      expect(described_class.parse("es-419")).to eql(described_class.new("es", "419", nil))
+      expect(described_class.parse("es-419")).to eql(described_class.new("es", nil, "419"))
     end
 
     describe "raises a ParserError when given" do
@@ -42,13 +42,13 @@ describe Locale do
 
     it "raises a ParserError when one of the arguments does not match the locale format" do
       expect { described_class.new("ZH", nil, nil) }.to raise_error(Locale::ParserError)
-      expect { described_class.new(nil, "cn", nil) }.to raise_error(Locale::ParserError)
-      expect { described_class.new(nil, nil, "hans") }.to raise_error(Locale::ParserError)
+      expect { described_class.new(nil, "hans", nil) }.to raise_error(Locale::ParserError)
+      expect { described_class.new(nil, nil, "cn") }.to raise_error(Locale::ParserError)
     end
   end
 
   describe "#include?" do
-    subject { described_class.new("zh", "CN", "Hans") }
+    subject { described_class.new("zh", "Hans", "CN") }
 
     it { is_expected.to include("zh") }
     it { is_expected.to include("zh-CN") }
@@ -59,7 +59,7 @@ describe Locale do
   end
 
   describe "#eql?" do
-    subject(:locale) { described_class.new("zh", "CN", "Hans") }
+    subject(:locale) { described_class.new("zh", "Hans", "CN") }
 
     context "when all parts match" do
       it { is_expected.to eql("zh-Hans-CN") }
@@ -84,9 +84,9 @@ describe Locale do
     let(:locale_groups) { [["zh"], ["zh-TW"]] }
 
     it "finds best matching language code, independent of order" do
-      expect(described_class.new("zh", "TW", nil).detect(locale_groups)).to eql(["zh-TW"])
-      expect(described_class.new("zh", "TW", nil).detect(locale_groups.reverse)).to eql(["zh-TW"])
-      expect(described_class.new("zh", "CN", "Hans").detect(locale_groups)).to eql(["zh"])
+      expect(described_class.new("zh", nil, "TW").detect(locale_groups)).to eql(["zh-TW"])
+      expect(described_class.new("zh", nil, "TW").detect(locale_groups.reverse)).to eql(["zh-TW"])
+      expect(described_class.new("zh", "Hans", "CN").detect(locale_groups)).to eql(["zh"])
     end
   end
 end