On December 2012, eight Europeans states have legalized the same-sex marriage. They are: Belgium, Denmark, Iceland, Netherlands, Norway, Portugal, Spain and Sweden.
On the same date, other thirteen European states have legalized the same-sex civil unions or they grant them some rights. They are: Andorra, Austria, Czech Republic, Finland, France, Germany, Hungary, Ireland, Liechtenstein, Luxembourg, Slovenia, Switzerland and the United Kingdom.
In the rest of Europe, the same-sex marriage or same-sex civil unions are not legally recognized.
Check the situation of same-sex marriage in USA
Check the situation of same-sex marriage in the rest of the world