Ideally, there should be a separate website optimised for each geographical market and that means using a country code Top Level Domain (ccTLD) and corresponding website. For example, .ie for Ireland, .co.uk for the UK. pl for Poland etc. The ccTLD “tells” the search engines where your target market is.
In the absence of a ccTLD the search engines use the user’s IP address, the IP address of the server, language used on the site and addresses, phone numbers, to make a “best guess”. So the use of a .com, for instance, can make it very difficult to rank highly across multiple countries.
A practical workaround is to keep the .com but use subdirectories for each target market e.g. example/it for the Italian market, and tell the search engines (via Webmaster Tools) which country that particular subdirectory is targeting.
Then on your home page, allow the visitor to choose the relevant country by means of a dropdown or “flag” selection. Importantly, this may mean creating content in the relevant languages (Google Translate is not recommended!). To optimise the site, these subdirectories should have some localised content as well as the local contact details.
Using the Hreflang Tag for pages in different languages
The hreflang tag is used to show search engines what the relationship is between web pages in different languages. It’s useful when you’ve created content that’s specific to a local audience.
For example, if you create an Italian language version of your homepage, you would tag it as “Italiano” by using hreflang=”it” so that searchers with an IP address that a search engine believes is in a Italian speaking country are served that page in Italian.
What the hreflang tag looks like:
If a particular region is particularly important then it might be worth considering using the ccTLD for that country.
The bottom line is that content delivery needs to be tailored to the target market and potential users. A “one size fits all” approach, while minimising the site administration, will ultimately dilute your market penetration.