I don't know about how easy it was to get loans in other countries -- somehow I doubt it was like here. But European hedge funds and banks could buy the "paper" as investments.
We have regulations dealing with banks, but as far as I know, these independent lenders that were not banks, had little or no regulation. These lenders did not have "deposits". They had lines of credit from hedge funds (also unregulated) and investment banks, and simply lent out the money to home buyers; then sold the paper to pension funds, other hedge funds, banks, etc. All diced and sliced, these packages of loans got high ratings from the rating agencies (also unregulated) which led investors to believe they were "safe."
All lending standards went out the window. People did not have to prove their assets or income, or put down any of their own money to buy a house. People lied to get loans; appraisers lied to get business, claiming they were pressured by the lenders to have an appraisal come in at a certain number so the deal could be done. There's alot of blame to go around.