Governments produce a wide array of publications ranging from bills, debates, hearings and reports to agency research publications, maps and posters. Plus there is census and statistical data, speeches, scientific studies, propaganda, diplomatic correspondence and more.
As primary sources these official governmental publications provide insight into all aspects of history from social issues to politics, from cultural mores to scientific endeavor.
The UW Libraries has an extensive collection British government documents. These documents are usually primary sources and can include Parliamentary Papers, Hansard's Parliamentary debates and Colonial Office reports. Most government material is housed in the Government Publications section on the ground floor of Suzzallo Library. Librarians there can help you find material you need.