The noun people is very unusual in English. It can take singular or plural verb forms and can have its own plural form peoples. As I say in A Guide to English Language Usage:
person and people
For almost all purposes people is the effective plural of person. It can follow a number and takes a plural verb: 1,500 people have bought tickets; the people who were (not was) present. However, people is not plural in origin. It comes from Latin populus, and has its own singular and plural forms corresponding to community, tribe, race, nation or ethnic group. So it is perfectly correct to speak of a warlike people; a peace-loving people; the peoples of Europe; Winston Churchill wrote A History of the English-Speaking Peoples.
Today’s Observer has an article about the elections to beheld in Catalonia on 25 November. It says of the governing CiU party:
The campaign slogan is “the people's will”.
Not quite. In Catalan it is La voluntat d’un poble and there we have the Catalan version of that Latin populus. It is unquestionably used in the singular form, equivalent to French peuple or German Volk. It could be argued that the people’s will means the will of the people, with people being understood a singular. But that is not quite right since the Catalan has the indefinite article, and in any case the use of people in English in such contexts is usually parsed as plural even when there is no clear indication one way or the other.
This blog is about language. Comments on the use of people singular or plural are welcome. Comments about the Catalan election itself are not welcome.