It was Passover in Jerusalem. Jesus, a practicing Jew, and his twelve followers (called disciples) would celebrate the annual religious holiday in the city.
At the time, Israel (then called Judea) was a Roman province. Although Caesar allowed the Jews to worship God according to their own religious laws, he (and the Romans) believed the Jews were atheists. (How, the thinking went, could anyone believe in only one God? And why were Jewish people forbidden to create images of their God?)
To understand the background of The Passion of the Christ, we need to look at life in first-century Israel. How did Rome come to control Judea in the first place?