In 1963–64, William Scott lived in Berlin on a DAAD (German Academic Exchange Service) fellowship. He began there in 1964 a series of ‘Blue paintings’, which came to be called ‘Berlin Blues’ (fig. 1). ‘The title has no significance apart from the discovery of this particular blue pigment in Berlin’, Scott explained in 1965. With reference to the composition of these paintings, he went on, ‘My space relationships have become more symmetrical i.e. more Byzantine in origin.’ The series belongs to Scott’s second abstract phase, which lasted between roughly 1964 and 1969, a decade after the first in 1952–54. Expanded was painted using a narrow, polarised palette of blue, white and green. These colours operate in a figure-ground relationship: white predominates and creates a broad field against which the forms of green and blue project forwards. Most of the Berlin Blues paintings were made on square-proportioned canvases, as in the case of Expanded, partly because of an aspiration to excise the horizon line and create more pithy, symbol-rich paintings, free from external reference points. The balloon-like figure at the centre of the painting is a poignant image, an untranslatable hieroglyph. The round-corned triangle beside it has similarly primitivist connotations. These include flint arrow heads and simple directional instructions (up/down, forward/back), though it may also be considered a mannerist sharpening of the archetypal bowl-like silhouette used to represent vessels in Scott’s earlier still-life paintings.

The curator and art historian Ronald Alley gave this appraisal of the Berlin Blues paintings:

"Instead of having rich, fatty pigment and a rough paint surface, the paint was applied thinly and evenly by a process akin to staining. The shapes became more regular and curvilinear, and were grouped so as to create rhythmical repetitions and contrasts, and changes of direction; these pictures had rather crowded compositions, with a number of large blue forms suspended in a milky white ground."

The foundation for the Berlin Blues series was Scott’s mural commission for the new Altnagelvin hospital in Londonderry. He worked on the project from 1959 to 1961, and the immense size of the work—over thirteen metres in width—precipitated significant developments in his painting. Speaking in 1974, he explained:

"I had again a reversal of attitude, due, I think, to working on a mural during the previous two years. My paintings became more flat and again close to some of the very simple, almost minimal statements that I had made ten years before. Related directly to the mural is the Berlin Blues series […]. In this group, the color [sic] is strong blue, and each picture has a repetitive theme that implies my concern at this time with my attitude to mural as well as public art. I felt relieved that I could expand and go beyond the ties of easel painting."