The Nordic societies can be characterized as countries with rather subtile class differences. To define which class people belong to has become harder in the last 50 years, when the democracy has led to compulsory education and social insurances for everyone. Equality has been the slogan best remembered from the French revolution, and strong labor unions have achieved many of their goals, with for instance manual workers often earning well as much as lower officials and teachers. Liberalism and Socialism are in Europe basically defined as ideas with a great deal of heritage from early Liberal and Socialistic writers. Liberalism could be said to revolve around freedom from the power of the mighty, and Socialism around freedom from the power of the rich.
Democratic freedom is per definition a Liberal virtue.
Some Social democrats might be classified as much of a Liberal, but most are definitely not. The program of the Social Democratic parties are not understood as Liberal, but when it comes to practical pragmatic politics and policies the outcome might be a mixture between the own program and other ideas. Conservatism is likewise defined as ideas succeeding the writings of Burke, Disraeli and other classical political writers. Socialism is the people's control over the means of production. High spending government is something different.