Answer the question from the given passage. Your answer should be directly extracted from the passage, and it should be a single entity, name, or number, not a sentence.

Passage: Cultural imperialism is when a country's influence is felt in social and cultural circles, i.e. its soft power, such that it changes the moral, cultural and societal worldview of another. This is more than just 'foreign' music, television or film becoming popular with young people, but that popular culture changing their own expectations of life and their desire for their own country to become more like the foreign country depicted. For example, depictions of opulent American lifestyles in the soap opera Dallas during the Cold War changed the expectations of Romanians; a more recent example is the influence of smuggled South Korean drama series in North Korea. The importance of soft power is not lost on authoritarian regimes, fighting such influence with bans on foreign popular culture, control of the internet and unauthorised satellite dishes etc. Nor is such a usage of culture recent, as part of Roman imperialism local elites would be exposed to the benefits and luxuries of Roman culture and lifestyle, with the aim that they would then become willing participants. Question: Which historic empire used cultural imperialism to sway local elites?
Roman