This debt, at least in Norways case, is probably mostly due to a very large portion of people buying their own home. Its a lot more common here than in other countries and when growing up, at some point buying your own home is almost expected of you. It is also heavily incentivized by the government through tax policy. This is probably creating a housing bubble of sorts, so i guess we'll see how well that turns out at some later date, but i assume that is the reason Norway is where it is on that chart.

I doubt Norwegian homeownership culture is anything as militant or debt-fueled as America's. Remember how the US nearly tanked itself with mortgage backed securities a few years ago?

As @farrisbris mentioned, this is mortgage based debt (in the Netherlands).

All debt is tracked, including the 'free' phone you get with your subscription. You can't go over a limit based on your income.

Also a large difference with for example the US is that in the Netherlands you don't need a down payment when buying a home. And until recently you could include the transfer tax, realtor, etc in the mortgage. All which make it easier to buy a home and thereby driving up the debt of a household.

Those countries have nowhere near the same consumerism culture as the United States.

With respect, that's a horrible generalization, and does nothing to refute my point that households Europe are in much more debt (as a share of disposable income) than US households.