Melbourne recently got the top spot in the Economist Intelligence Unit's Global Liveability Index, out of 150 capitals. It's the fourth time the city's been named number one in that survey, and it was joined by Sydney, Adelaide and Perth in the top 10. Melbourne rated highly in health care, education and infrastructure. Melbourne is also Australia's most culturally diverse city, with migrants, or those born to migrants, accounting for nearly half of all Victorians. So what role did multiculturalism play in its "liveability"?