What is the Empire?

I have a very vague understanding of the Empire. For my understanding of what we discussed in class, the Empire was located in what is now Germany/ Austria/ Czech Republic. They have been around for hundreds of years fighting wars for land and power. The Empire has extended its reign from Finland to Spain and even some parts of South America. The assassination Archduke Ferdinand was the catalyst that started World War I. After World War II the victors of the war split up the Empire into different countries which are the ones I previously mentioned.