I live overseas now and I just found out that you do need a pet passport to travel into any of the European countries. They have to have all shots up to date, a health certificate no more then 10 days before your travel date, and also there is NO quarantine period to bring pets over here or even back to the states. But if you want to check it out and what regulations there are you can look at
www.travel.state.gov. It has all the info that you need to travel over to Europe.