subdomain/locale controller, view issue

gistfile1.rb

=begin
I've run into an architectural challenge. I'm hoping some second opinions will help me organize this logic.

My sites naked and www domains serve as entrypoints to numerous subdomains through which users interact with the site.
=end
models/region.rb
class Region < ActiveRecord::Base
  ...
end

lib/subdomain.rb
class Subdomain
  def self.matches?(request)
    request.subdomain.present? && request.subdomain != 'www' &&
      Region.active_subdomain?(request.subdomain)
  end
end

# I've placed logic about which subdomain a user has visited in a class called Locale.

lib/locale.rb
class Locale

  # must provide session and request options
  def initialize(options = {})

    raise ArgumentError, 'No session provided' if options[:session].nil?
    raise ArgumentError, 'No request provided' if options[:request].nil?

    @region = case
    when Subdomain.matches?(options[:request])
      region = Region.find_by_subdomain(options[:request].subdomain)
      options[:session][:region_id] = region.id
      region # @region = region
    else
      Region.find_by_id(options[:session][:region_id]) || Region.new
    end

  end

  # return the region object associated with this Locale
  def region
    @region
  end

  def valid?
    @region.present?
  end

end

# Then I place a before_filter in Application controller so Locale gets set up for every request.

class ApplicationController < ActionController::Base
  include LocaleHelper
  protect_from_forgery

  prepend_before_filter :set_locale

  helper_method :within_region?
  helper_method :initialize_data_for_listings_form

  def set_locale
    @locale = Locale.new(request: request, session: session)
  end

  def within_region?
    Subdomain.matches?(request)
  end

  # send return visitors on their way
  def redirect_return_visitors
    return if @locale.nil? || @locale.valid? == false
    r = Region.find_by_id(@locale.region.id)
    saved_region = url_for subdomain: r.subdomain,
      controller: 'listings', action: 'index'

    redirect_to saved_region if return_visitor?
  end

  def render_404(message = "page not found")
    raise ActionController::RoutingError.new(message)
  end

  def reject_unless_current_user_is_admin
    render_404 unless current_user.is_admin?
  end

  def reject_unless_current_region_set
    # TODO to root
    redirect_to '/' if @locale.region == nil
  end

  def initialize_data_for_listings_form(controller)
    models = Category.major.sort_by! { |c| c.name }
    cvar = :@major_categories
    controller.instance_variable_set(cvar, models)

    regions = Region.find(@locale.region.id).leaves
    regions.sort_by! { |r| r.name }
    rvar = :@regions
    controller.instance_variable_set(rvar, regions)
  end

end

# Here is the locale functionality in use.

# locale in use dot rbs (some html.hamls)
# first:
        - if within_region?
          = @locale.region.name

# second:
    %title= "sitename #{@locale.region.name}"

# third:
    #region-step.step
      %h1 Where in #{@locale.region.name}?
      %hr
      = f.association :region, as: :select, label: false,
        input_html: { id: 'select-region'},
        collection: @regions
      %hr

# fourth:
  def initialize_data_for_listings_form(controller)
    models = Category.major.sort_by! { |c| c.name }
    cvar = :@major_categories
    controller.instance_variable_set(cvar, models)

    regions = Region.find(@locale.region.id).leaves
    regions.sort_by! { |r| r.name }
    rvar = :@regions
    controller.instance_variable_set(rvar, regions)
  end

the problem is, the first time someone visits the site, they haven't yet visited a particualr region, so @locale.region is nil. This causes application errors.

I've considered extending application_controller with a module called LocaleHelper to address this.

lib/locale_helper.rb
def current_region_name
  if @locale.present? && @locale.region.present?
    @locale.region.name
  else
    ''
  end
end

def current_region_id
  if @locale.present? && @locale.region.present?
    @locale.region.id
  else
    ''
  end
end

I'm sure there's a better way to accomplish this. Any ideas?