1912 - 19210
George Braque and Pablo Picasso excelled the medium into the Fine Arts world by creating two-dimensional paper collages according to the principles of cubism, exploring newspapers, clippings and tobacco papers and combining them with paint or charcoal. After the cubists had entered into the medium, other artist movements around the world rapidly recognized the variety of possibilities provided by this new way of artistic expression. Soon Italian Futurists used this new channel of expression to display ideals of the machine age, Russian constructivists to show details of the Russian revolution
1920 - 1940
The Dadaists and Surrealists began to stretch the boundaries of the medium, the most well known Dadaist, Marcel Duchamp, created his famous "ready-mades" based on collage principles combining found objects with added text. Another Dadaists, Hannah Hoech, Kurt Schwitters and Max Ernst integrated common daily objects of life like letters or tickets or explored themes from the field of psychiatry such as conscious mind's control elements to release subconscious images (Max Ernst was famous for a style of damaging images through peeling or tearing) and created social critique guided art. Hilla von Rebay, known as a Guggenheim co-founder, created beautiful collages after committing to truly abstract themes around the 1920's.
1940 - 1950
During the 1940's Joseph Cornell took the two dimensional collage to a new level, the assemblages (Assemblages are three-dimensional cousins of collage in which the artist assembles and displays found objects). In the same time period, abstract expressionists such as Robert Motherwell used collage to generate abstract shapes from daily life printed advertising such as soap boxes, bottle labels or cigarette packages. While Motherwell used Collage in a playful way to be spontaneous, Robert Rauschenberg explored it to challenge the expressionists devotion to abstract themes in his "combine paintings", best know is probably "Bed" featuring a mattress and painted bedclothes
1950 - 1960
Jasper Johns continued the collage theme with three dimensional pieces such as dartboards and other large objects embellishing his work like the cubists with paint.
In the 1960's, collage artists focused on items that represented pop culture such as advertisements, comic strips and food packaging by transforming or spoofing them to give them a new life of their own. An example of this period are Claes Oldenberg's large scale sculptures using everyday objects in unusual materials, like a huge Ice cream cone in Fabric.
Recent
More recently, Neo-Expressionists began incorporating collage elements into painted surfaces. Examples here are Julian Schnabel or Jeff Koons.