I think it's more common in europe because the first industrial producer of chip card was created in France (Gemplus, now Gemalto). In France, payment cards are "dual network" : any card is either Visa OR Mastercard AND also "CB". "CB" is a payment network managed by the "GIE Carte Bancaire" owned by all french banks.

CB dealt with Gemplus to add chip to all new cards emitted since 1992 so we had them for a long time. I don't know how it spread over europe, but as we had the industrial capacity to provide chip cards to everyone and a free market, I think it was easy to sell that to lots of european banks. CHIP+PIN is a really great deal for banks : it's cheap and the responsibility of all payments made with the PIN is on the card owner and are really hard (or impossible) to dispute.

In the US, interchange fees are an order of magnitude more than in the EU, where they are capped. So there is a lot more fraud the system can silently swallow before anyone has to consider upsetting customers and vendors with PINs.

I thought it was the US that was still considered a hot bed for card fraud.

I've been to stores in the US where they just swipe your magstrip and hand you back the card. No signature, no pin, they don't even look at it, so you can basically clone cards like it's still 1985.

This is consistent with how my UK bank treats any transaction occurring in the US: usually it's an instant card block and a polite phone call from them to check that it was actually me.

In the UK it's mostly likely because of EU regulations. I've never had anything but chip and pin in the EU, got my first card ~2006