I'll tell you the answer on this page. First, I don't really like the word "pet" but have used it in the title because that is what the general public are more likely to search for rather than "which country loves cats the most?". My research comes from Google's excellent statistics in relation to this website, which is mainly about cats. So, I'll tell you which country, or more accurately, the people of which country are most interested in the domestic cat. As people worldwide like cats and dogs in about equal measure the figures should also apply to dogs and therefore pets generally.
One factor that might bend the figures is language. This site is in English and some countries speak English as their first language. However Google translation is pretty good these days.
If we take a sample size of say 100 people from across the world who come to this website, 67 of them would be from the United States of America. And about 15 of the people would be from the United Kingdom.
One country not featuring on this list but which would feature on other lists is Russia. The Russian people like their cats and have quite a nice cat fancy. A number of cat breeds originate in Russia including the Siberian, Russian Blue and Kurilian Bobtail to name three. They would normally occupy at least 5% of the visitors.
The overwhelming number comes from the USA. Germany, where they speak good English has a low representation. One person out of the 100 visits from Germany. And France are just not on the map. Europe as a whole (excluding the UK) show themselves as not that interested in pets or at least not reading about them.
In relation to the size of the country the UK punches well above its weight. The UK has a population that is about twice that of California, just one of the 50 states on the US and yet occupies second place on this list. On the basis if this analysis the UK has a much greater proportion of its people who are interested in the domestic cat than the USA.
India is interesting. It is country that is becoming increasingly interested in keeping the domestic cat. I think they'll have a cat fancy there one day.
Australia is known to have a interest in the domestic cat but the interest is somewhat schizophrenic as the people of Australia in general hate the feral cat as they think it decimates their native wild species. As feral cats were once domestic cats it is a rather odd relationship.
The same could be said about the United States. There is no doubt that they are the major country of cat and pet lovers in terms of overall numbers. They lead the world by a considerable margin because they are a large country. However, rather like Australia they have a schizophrenic relationship with the domestic cat. They declaw cats. They kill cats by the millions every year because they are homeless. I won't go on. And I am not criticising - just reporting.
Conclusion: The UK, and particularly England is the leading nation of pet lovers. Also the laws of England, Wales and N. Ireland are probably the best in relation to animal welfare (
Animal Welfare Act 2006).