I don't know what the timescale on writing the paper is, but if you have some time a great start would be Noel Cowen's Global History, a short overview. In this work Cowen analyzes the history of the world in a global perspective, starting in the ancient period with the transition from nomadic hunte/gatherers to settled farmers and analyzing the ancient empires before moving on to more modern empirebuilding.

Of particular interest, at least in my opinion, is the chapter labeled 'the religious factor'. In this chapter he describes the ways in wich empires used religion as a stabilising factor, but also how religion inevitably ended up transcending political borders. The rise of christianity is of course a great potential subject here, but other possibility's include Alexander the Greats Hellenism, Persian Zoroastrianism and Buddhism in India.

If you want a more modern subject you could also go for stuff like the impact of technology on the rise of a globalised economy (and make no mistake, this is by no means a recent thing) or maybe even make a comparison between the aforementioned role of religion in ancient empires and the role of ideology in more modern ones.