Rome was a powerful and huge empire for a long time, which controlled most of Europe. It is important for many reasons. First, the Ancient Romans have influenced world’s culture and made a huge impact on the development of technology and science. Secondly, Roman Empire had a great political significance, since Romans were the first who created a Senate.
The purpose of a ziggurat was to create a place for deity - it had many levels and it was a huge temple. Each level was a sub-temple for less important gods, while the highest level was believed to be a place reserved for the most important god.