Eastern Europe and Former Soviet Union
In the 1990s, when the Berlin Wall came down, everything changed in Eastern Europe and the former Soviet Union. Countries that once were communist became democratic, and the Soviet Union itself dissolved into many individual nations. Despite the change in the country's name or its government's approach to governing, many of the manners and customs of old remain. Don't be offended if in certain countries, like Russia or the Czech Republic, people seem a bit standoffish at first. On the other hand, in countries like Poland and Hungary, you shouldn't be taken aback if someone you've just met greets you with a hug and a kiss on both cheeks. To remain in your host's good graces, follow his lead. You can't go wrong with this approach.
Raising a Glass
Drinking alcohol and toasting one another is a big part of being social in Eastern European countries and the nations that used to be the Soviet Union. Again, follow your host's lead. You should only take a taste of your drink after the host has offered his toast and never before.
Keep in mind that while Russians will raise a glass of anything alcoholic for a toast, in countries like Poland, you only toast when holding a glass of vodka, and in Hungary, you never clink your glasses together for a toast.
Religions to Consider
Most of the countries in this region of the world have a Christian-based religion. The one exception to the rule are the Muslims who live in the former Yugoslavia. Their holiest holiday is the month-long celebration of Ramadan, which requires fasting during the day. (People eat and drink at night.) If you're visiting this region or any other Muslim country during Ramadan, you will show the locals great respect by abstaining from eating, drinking, and smoking in public during daylight hours.
The Native Tongue
Folks in these countries appreciate that their collective languages are hard to understand and even harder to speak. But unlike some Western European countries, residents here will get a real kick out of it if you attempt to speak their language, even if it's only to say “Hello” or “Thank you.” Graciousness and courtesy go a long way, and trying to speak a foreign language, albeit not well, shows people you are interested in their culture and customs.