I have recently published a partial translation of a Firefox international market share study. While the numbers are very impressive, one could wonder why they are so different from one country to the other. Many people in the Mozilla project contacted me to discuss this topic. And frankly, I don't know the reason why the numbers are so different around the world, but I have a few ideas that I'd like to share with my readers.
It's about the adoption level
Some countries are more advanced on the technology front than others. For example, European Nordic countries are usually more advanced than Mediterranean countries (but let's not do too much of generalization). And it looks like there is some level of correlation, where more technologically-advanced countries have a better Firefox adoption. But this this not the only explanation.
It's about the language barriers
It's true that since technology (and particularly software) is often available in English first, and then in native language, countries where English understanding is widespread are likely to adopt new products like Firefox faster than countries which are not particularly keen on English, such as Spain or Portugal.
It's about Microsoft
Microsoft has more success in some countries than others. There are regions where Microsoft has virtually eliminated all competition on the local market. For example, I am told that Apple is not doing very well in Spain, for example. In such countries, the market is used to deal with a monopoly (including paying a higher price because of the lack of choice) and the very notion of choice is not on people's mind. Some other countries, such as Germany, have historically loyal to Netscape for some reason, and even in 2001, Netscape 4 still had 15% market share on this market (YMMV), while in most other countries Netscape only had around 5%. In such countries, innovative, non-Microsoft products have higher chances to succeed.
It's about Open-source philosophy
Some countries are more willing to adopt Open-Source solutions than others. In some cases politicians want to adopt them and in other cases are leaning more to a proprietary approach. Ingrid Marson, of ZDNet UK, has recently published an interesting set of articles on this very topic: Europe and the US philosophically divided on open source?. Ingrid goes into details about Germany, Poland and Eastern Europe, Spain, Norway, UK, US, and France.
It's about local communities
In some countries, local communities are more vibrant than in others. I won't give any examples, because I know they all do their best, but it's a fact that having a local energetic leader, along with numerous volunteers, is a huge asset to promote Firefox in a more efficient way.
Conclusion
All in all, it's for sure a mix of all the reasons that I mentioned, plus several other factors that I don't know of (or which I forgot to mention here). I wish I had a definitive answer or even the ultimate recipe for Firefox success in every country, but I just don't 
So we, at Mozilla Europe, do the best we can to have products in all local languages, along with an official, well-maintained Web site (now in 20 languages!), and vibrant communities (developers, localizers and enthusiasts).
