As one of the world's most technologically advanced nations, Japan might seem an obvious market for Facebook. It has the world's second highest number of social media users, after the United States, according to the Nielsen Company. And users have enthusiastically embraced trends such as microblogging and social gaming.
Yet until recently, Facebook failed to make an impact. The Asian country, together with South Korea, Russia, and China (where it is still banned) were notable gaps on its map of world dominance.
In January 2011, it only had 2 million Japanese users - less than 2 per cent of the country's online population. Users overwhelmingly preferred Mixi, a home-grown competitor, which had 21 million users at the same time.
There were several reasons for this. Mixi was already established as market leader when Facebook launched its first localized version. And in the rush to expand, marketers had overlooked some key aspects of Japanese culture.
Firstly, Facebook was poorly optimized for the Japanese language. The company had rolled out a crowd-sourced translated version, but many users complained about the quality. They said the layout and language made it difficult to use.
The site also insisted users used their correct names - which was out of step with cultural norms. People tend to be more concerned with protecting their privacy and reluctant to diverge personal information, particularly in a public sphere. The idea of tagging photos or posting public messages was also seen as unnecessarily intrusive.
Mixi was found to be a simpler to use, with an easy way of sharing blogs and photos. Users trusted the network with their personal details. And most importantly, their friends were on it - meaning there was no compelling reason to switch.
So why has this changed? One reason is the company has made a huge push in Japan, expanding its staff in Tokyo and changing the language and layout to make it more localized.
Businesses also began to embrace the idea of fan pages. Not only was this an informal way for users to connect with their favourite brands, but more companies were using the network for recruitment. This gave recent graduates and jobseekers a strong incentive to get on board. The film, the Social Network, also gave the company a boost in Japan, despite its unflattering portrayal of its founders.
Surprisingly, last year's devastating earthquake and tsunami gave users another reason to use the networking site. With telephone lines and cellphone masts down, people found its "real names" policy useful for keeping in touch with friends and family and finding out information.
According to SocialBakers, Facebook now has almost 17 million users, representing 16.95 per cent of the online population. More impressively, it has seen growth of more than 7.7 million in the last six months. This makes it one of the fastest growing markets for the network.
Although Mixi boasts 26 million registered users, it falls behind on the number of active users - with only around 14.5 million accessing the site at least once a month. It has been slow to adapt to new trends - for example, only recently adding social games to the site.
Facebook plans to continue its focus on this market. Its reach is still relatively low compared to other countries, Chief Operating Office Sheryl Sandberg stressed its importance on a recent visit to Tokyo, saying they're keen to increase their share of its huge advertising market. One big challenge will be taking advantage of Japanese users' advanced use of the mobile internet.
Of course there are still challenges to overcome. Its reach is still relatively low compared to other countries, with just 29 per cent of social media users. This compares to 67.2 per cent in the USA.
And it has another huge rival in Twitter, which has an estimated 18 million users in the country. Winning this battle won't be easy. Twitter CEO Dick Costolo is said to be "aggressively" hiring more sales staff to cash in on its pole position. And it has recently joined Mixi to offer joint advertising opportunities across both networks.