Mackintosh was born in Glasgow and his work is concentrated there. His career coincided with Glasgow's economic boom. By the end of the 19th century Glasgow was a wealthy city with trade links around the world, so it was a rich source of commissions for an architect and designer.
Mackintosh developed a decorative style based on black and white grid patterns, over which he laid sweeping sinuous lines [Fig. 1]. His use of line is very similar to Art Nouveau, but the underlying grid is original and it makes his work more relentlessly modern than most Art Nouveau. There is a stylised treatment of nature. Stylised flowers were a trademark; they are very reminiscent of calligraphy.

Fig. 1 Mackintosh window design
His chairs often used a grid pattern influenced by Japanese design [Fig. 2]. It is much more rectilinear that most Art Nouveau, but the back is elongated, which makes it very elegant. These wardrobes have a very sculptural form. They're white, which was very unusual at the time; it seems to reduce their mass. There is a small passage of colour with the usual linear patterns and rose motifs.

Fig. 2 Mackintosh furniture
Like most Art Nouveau, Mackintosh's work expressed a unity of the arts. He designed interiors which unify architecture, furniture and decoration. In the 1890s he was commissioned to design a decorative scheme by Kate Cranston, who owned a number of "artisitic" tea rooms in Glasgow [Fig. 3]. There was the Buchanan Street Tea Rooms (1896-7), Argyle Street (1897), Ingram Street (1901) and Willow Tea Rooms (1903-4). He designed a complete decorative scheme for each one. He designed everything from furniture and menus to the waitresses' uniforms. Art, architecture and design were unified in a complete environment that was light, elegant and sophisticated.

Fig. 3 Buchanan Street Tea Room
Mackintosh was also a talented architect. In this field, his greatest achievement was the Glasgow School of Art (1897-9). The whole building is built of grim local stone, which is resilient to the harsh climate and redolent of a sense of the Scottish vernacular traditions [Fig. 4]. The east face has sheer walls, very stark and brutal like in a Scottish castle. Mackintosh's work has a stronger sense of national identity than was typical of Art Nouveau. But it also has projecting windows encased in glass, which were incredibly modernistic.

Fig. 4 Glasgow School of Art
The School has an austere and asymmetrical north façade with large windows to illuminate the studios [Fig. 5]. It is marked by strong spatial massing.
The entrance is an abstract interlocking of forms. The treatment is very sculptural. Mackintosh has cut away at the wall to give this interplay of void and volume. There's also curvilinear ironwork and stone work, which is pure Art Nouveau. These iron brackets on the windows are knots of metal like the famous rose motif.

Fig. 5 Glasgow School of Art - entrance
One of Mackintosh's best interiors is the library [Fig. 6]. This has a complex gallery designed on a three-dimensional grid pattern. Suspended light fittings with stained glass give it a transcendental atmosphere. The central fall of light from the windows contrasts with the dark wood.

Fig. 6 Glasgow School of Art - library