diff --git a/db/migrate/20180323190027_add_translate_milestones.rb b/db/migrate/20180323190027_add_translate_milestones.rb
index 6e27583a8e9..6767d8e8423 100644
--- a/db/migrate/20180323190027_add_translate_milestones.rb
+++ b/db/migrate/20180323190027_add_translate_milestones.rb
@@ -1,9 +1,12 @@
 class AddTranslateMilestones < ActiveRecord::Migration
   def self.up
-    Budget::Investment::Milestone.create_translation_table!({
-      title: :string,
-      description: :text
-    })
+    Budget::Investment::Milestone.create_translation_table!(
+      {
+        title:       :string,
+        description: :text
+      },
+      { migrate_data: true }
+    )
   end
 
   def self.down
diff --git a/db/migrate/20180718115545_create_i18n_content_translations.rb b/db/migrate/20180718115545_create_i18n_content_translations.rb
index e472f06222e..8e6fde21cf5 100644
--- a/db/migrate/20180718115545_create_i18n_content_translations.rb
+++ b/db/migrate/20180718115545_create_i18n_content_translations.rb
@@ -6,7 +6,10 @@ def change
 
     reversible do |dir|
       dir.up do
-        I18nContent.create_translation_table! :value => :text
+        I18nContent.create_translation_table!(
+          { value: :text },
+          { migrate_data: true }
+        )
       end
 
       dir.down do
diff --git a/db/migrate/20180727140800_add_banner_translations.rb b/db/migrate/20180727140800_add_banner_translations.rb
index 7678a34a105..4c4c9391edb 100644
--- a/db/migrate/20180727140800_add_banner_translations.rb
+++ b/db/migrate/20180727140800_add_banner_translations.rb
@@ -2,8 +2,11 @@ class AddBannerTranslations < ActiveRecord::Migration
 
   def self.up
     Banner.create_translation_table!(
-      title:       :string,
-      description: :text
+      {
+        title:       :string,
+        description: :text
+      },
+      { migrate_data: true }
     )
   end
 
diff --git a/db/migrate/20180730120800_add_homepage_content_translations.rb b/db/migrate/20180730120800_add_homepage_content_translations.rb
index 41596453622..b344f95c347 100644
--- a/db/migrate/20180730120800_add_homepage_content_translations.rb
+++ b/db/migrate/20180730120800_add_homepage_content_translations.rb
@@ -2,10 +2,13 @@ class AddHomepageContentTranslations < ActiveRecord::Migration
 
   def self.up
     Widget::Card.create_translation_table!(
-      label:       :string,
-      title:       :string,
-      description: :text,
-      link_text:   :string
+      {
+        label:       :string,
+        title:       :string,
+        description: :text,
+        link_text:   :string
+      },
+      { migrate_data: true }
     )
   end
 
diff --git a/db/migrate/20180730213824_add_poll_translations.rb b/db/migrate/20180730213824_add_poll_translations.rb
index 4a4fa72a4df..75495d3272c 100644
--- a/db/migrate/20180730213824_add_poll_translations.rb
+++ b/db/migrate/20180730213824_add_poll_translations.rb
@@ -2,9 +2,12 @@ class AddPollTranslations < ActiveRecord::Migration
 
   def self.up
     Poll.create_translation_table!(
-      name:        :string,
-      summary:     :text,
-      description: :text
+      {
+        name:        :string,
+        summary:     :text,
+        description: :text
+      },
+      { migrate_data: true }
     )
   end
 
diff --git a/db/migrate/20180731150800_add_admin_notification_translations.rb b/db/migrate/20180731150800_add_admin_notification_translations.rb
index 519751fd7b1..fb76a42d29a 100644
--- a/db/migrate/20180731150800_add_admin_notification_translations.rb
+++ b/db/migrate/20180731150800_add_admin_notification_translations.rb
@@ -2,8 +2,11 @@ class AddAdminNotificationTranslations < ActiveRecord::Migration
 
   def self.up
     AdminNotification.create_translation_table!(
-      title: :string,
-      body:  :text
+      {
+        title: :string,
+        body:  :text
+      },
+      { migrate_data: true }
     )
   end
 
diff --git a/db/migrate/20180731173147_add_poll_question_translations.rb b/db/migrate/20180731173147_add_poll_question_translations.rb
index a167ea00a29..f62fbc1613d 100644
--- a/db/migrate/20180731173147_add_poll_question_translations.rb
+++ b/db/migrate/20180731173147_add_poll_question_translations.rb
@@ -2,7 +2,8 @@ class AddPollQuestionTranslations < ActiveRecord::Migration
 
   def self.up
     Poll::Question.create_translation_table!(
-      title: :string
+      { title: :string },
+      { migrate_data: true }
     )
   end
 
diff --git a/db/migrate/20180801114529_add_poll_question_answer_translations.rb b/db/migrate/20180801114529_add_poll_question_answer_translations.rb
index 91643f4433a..3203d7a1f51 100644
--- a/db/migrate/20180801114529_add_poll_question_answer_translations.rb
+++ b/db/migrate/20180801114529_add_poll_question_answer_translations.rb
@@ -2,8 +2,11 @@ class AddPollQuestionAnswerTranslations < ActiveRecord::Migration
 
   def self.up
     Poll::Question::Answer.create_translation_table!(
-      title:       :string,
-      description: :text
+      {
+        title:       :string,
+        description: :text
+      },
+      { migrate_data: true }
     )
   end
 
diff --git a/db/migrate/20180801140800_add_collaborative_legislation_translations.rb b/db/migrate/20180801140800_add_collaborative_legislation_translations.rb
index 7c0fb9eb32a..569689a73ce 100644
--- a/db/migrate/20180801140800_add_collaborative_legislation_translations.rb
+++ b/db/migrate/20180801140800_add_collaborative_legislation_translations.rb
@@ -2,25 +2,33 @@ class AddCollaborativeLegislationTranslations < ActiveRecord::Migration
 
   def self.up
     Legislation::Process.create_translation_table!(
-      title:           :string,
-      summary:         :text,
-      description:     :text,
-      additional_info: :text,
+      {
+        title:           :string,
+        summary:         :text,
+        description:     :text,
+        additional_info: :text,
+      },
+      { migrate_data: true }
     )
 
     Legislation::Question.create_translation_table!(
-      title:           :text
+      { title: :text },
+      { migrate_data: true }
     )
 
     Legislation::DraftVersion.create_translation_table!(
-      title:           :string,
-      changelog:       :text,
-      body:            :text,
-      body_html:       :text,
-      toc_html:        :text
+      {
+        title:     :string,
+        changelog: :text,
+        body:      :text,
+        body_html: :text,
+        toc_html:  :text
+      },
+      { migrate_data: true }
     )
     Legislation::QuestionOption.create_translation_table!(
-      value:           :string
+      { value: :string },
+      { migrate_data: true }
     )
   end
 
diff --git a/db/migrate/20180924071722_add_translate_pages.rb b/db/migrate/20180924071722_add_translate_pages.rb
index 6dc939dec00..250f46dee7d 100644
--- a/db/migrate/20180924071722_add_translate_pages.rb
+++ b/db/migrate/20180924071722_add_translate_pages.rb
@@ -1,10 +1,14 @@
 class AddTranslatePages < ActiveRecord::Migration
   def self.up
-    SiteCustomization::Page.create_translation_table!({
-      title: :string,
-      subtitle: :string,
-      content: :text
-    })
+    SiteCustomization::Page.create_translation_table!(
+      {
+        title:    :string,
+        subtitle: :string,
+        content:  :text
+      },
+      { migrate_data: true }
+    )
+
     change_column :site_customization_pages, :title, :string, :null => true
   end
 
diff --git a/lib/tasks/globalize.rake b/lib/tasks/globalize.rake
new file mode 100644
index 00000000000..51a23042e02
--- /dev/null
+++ b/lib/tasks/globalize.rake
@@ -0,0 +1,89 @@
+namespace :globalize do
+  def translatable_classes
+    [
+      AdminNotification,
+      Banner,
+      Budget::Investment::Milestone,
+      I18nContent,
+      Legislation::DraftVersion,
+      Legislation::Process,
+      Legislation::Question,
+      Legislation::QuestionOption,
+      Poll,
+      Poll::Question,
+      Poll::Question::Answer,
+      SiteCustomization::Page,
+      Widget::Card
+    ]
+  end
+
+  def migrate_data
+    @errored = false
+
+    translatable_classes.each do |model_class|
+      logger.info "Migrating #{model_class} data"
+
+      fields = model_class.translated_attribute_names
+
+      model_class.find_each do |record|
+        fields.each do |field|
+          locale = if model_class == SiteCustomization::Page && record.locale.present?
+                     record.locale
+                   else
+                     I18n.locale
+                   end
+
+          translated_field = record.localized_attr_name_for(field, locale)
+
+          if record.send(translated_field).blank?
+            record.send(:"#{translated_field}=", record.untranslated_attributes[field.to_s])
+          end
+        end
+
+        begin
+          record.save!
+        rescue ActiveRecord::RecordInvalid
+          logger.warn "Failed to save #{model_class} with id #{record.id}"
+          @errored = true
+        end
+      end
+    end
+  end
+
+  def logger
+    @logger ||= Logger.new(STDOUT).tap do |logger|
+      logger.formatter = proc { |severity, _datetime, _progname, msg| "#{severity} #{msg}\n" }
+    end
+  end
+
+  def errored?
+    @errored
+  end
+
+  desc "Simulates migrating existing data to translation tables"
+  task simulate_migrate_data: :environment do
+    logger.info "Starting migrate data simulation"
+
+    ActiveRecord::Base.transaction do
+      migrate_data
+      raise ActiveRecord::Rollback
+    end
+
+    if errored?
+      logger.warn "Some database records will not be migrated"
+    else
+      logger.info "Migrate data simulation ended successfully"
+    end
+  end
+
+  desc "Migrates existing data to translation tables"
+  task migrate_data: :environment do
+    logger.info "Starting data migration"
+    migrate_data
+    logger.info "Finished data migration"
+
+    if errored?
+      logger.warn "Some database records couldn't be migrated; please check the log messages"
+    end
+  end
+end
diff --git a/spec/lib/tasks/globalize_spec.rb b/spec/lib/tasks/globalize_spec.rb
new file mode 100644
index 00000000000..b685bb95e1d
--- /dev/null
+++ b/spec/lib/tasks/globalize_spec.rb
@@ -0,0 +1,168 @@
+require "rails_helper"
+require "rake"
+
+describe "Globalize tasks" do
+
+  describe "#migrate_data" do
+
+    before do
+      Rake.application.rake_require "tasks/globalize"
+      Rake::Task.define_task(:environment)
+    end
+
+    let :run_rake_task do
+      Rake::Task["globalize:migrate_data"].reenable
+      Rake.application.invoke_task "globalize:migrate_data"
+    end
+
+    context "Original data with no translated data" do
+      let(:poll) do
+        create(:poll).tap do |poll|
+          poll.translations.delete_all
+          poll.update_column(:name, "Original")
+          poll.reload
+        end
+      end
+
+      it "copies the original data" do
+        expect(poll.send(:"name_#{I18n.locale}")).to be nil
+        expect(poll.name).to eq("Original")
+
+        run_rake_task
+        poll.reload
+
+        expect(poll.name).to eq("Original")
+        expect(poll.send(:"name_#{I18n.locale}")).to eq("Original")
+      end
+    end
+
+    context "Original data with blank translated data" do
+      let(:banner) do
+        create(:banner).tap do |banner|
+          banner.update_column(:title, "Original")
+          banner.translations.first.update_column(:title, "")
+        end
+      end
+
+      it "copies the original data" do
+        expect(banner.title).to eq("")
+
+        run_rake_task
+        banner.reload
+
+        expect(banner.title).to eq("Original")
+        expect(banner.send(:"title_#{I18n.locale}")).to eq("Original")
+      end
+    end
+
+    context "Original data with translated data" do
+      let(:notification) do
+        create(:admin_notification, title: "Translated").tap do |notification|
+          notification.update_column(:title, "Original")
+        end
+      end
+
+      it "maintains the translated data" do
+        expect(notification.title).to eq("Translated")
+
+        run_rake_task
+        notification.reload
+
+        expect(notification.title).to eq("Translated")
+        expect(notification.send(:"title_#{I18n.locale}")).to eq("Translated")
+      end
+    end
+
+    context "Custom page with a different locale and no translations" do
+      let(:page) do
+        create(:site_customization_page, locale: :fr).tap do |page|
+          page.translations.delete_all
+          page.update_column(:title, "en Français")
+          page.reload
+        end
+      end
+
+      it "copies the original data to both the page's locale" do
+        expect(page.title).to eq("en Français")
+        expect(page.title_fr).to be nil
+        expect(page.send(:"title_#{I18n.locale}")).to be nil
+
+        run_rake_task
+        page.reload
+
+        expect(page.title).to eq("en Français")
+        expect(page.title_fr).to eq("en Français")
+        expect(page.send(:"title_#{I18n.locale}")).to be nil
+      end
+    end
+
+    context "Custom page with a different locale and existing translations" do
+      let(:page) do
+        create(:site_customization_page, title: "In English", locale: :fr).tap do |page|
+          page.update_column(:title, "en Français")
+        end
+      end
+
+      it "copies the original data to the page's locale" do
+        expect(page.title_fr).to be nil
+        expect(page.title).to eq("In English")
+
+        run_rake_task
+        page.reload
+
+        expect(page.title).to eq("In English")
+        expect(page.title_fr).to eq("en Français")
+        expect(page.send(:"title_#{I18n.locale}")).to eq("In English")
+      end
+    end
+
+    context "Invalid data" do
+      let!(:valid_process) do
+        create(:legislation_process).tap do |process|
+          process.translations.delete_all
+          process.update_column(:title, "Title")
+          process.reload
+        end
+      end
+
+      let!(:invalid_process) do
+        create(:legislation_process).tap do |process|
+          process.translations.delete_all
+          process.update_column(:title, "")
+          process.reload
+        end
+      end
+
+      it "ignores invalid data and migrates valid data" do
+        expect(valid_process).to be_valid
+        expect(invalid_process).not_to be_valid
+
+        run_rake_task
+
+        expect(valid_process.translations.count).to eq 1
+        expect(valid_process.reload.title).to eq "Title"
+
+        expect(invalid_process.translations.count).to eq 0
+        expect(invalid_process.reload.title).to eq ""
+      end
+    end
+
+    context "locale with non-underscored name" do
+      before { I18n.locale = :"pt-BR" }
+
+      let!(:milestone) do
+        create(:budget_investment_milestone).tap do |milestone|
+          milestone.translations.delete_all
+          milestone.update_column(:title, "Português")
+          milestone.reload
+        end
+      end
+
+      it "runs the migration successfully" do
+        run_rake_task
+
+        expect(milestone.reload.title).to eq "Português"
+      end
+    end
+  end
+end