Definition of "Modernism"

Oxford Dictionary

modern character or quality of thought, expression, or technique:
a strange mix of nostalgia and modernism

• a style or movement in the arts that aims to depart significantly from classical and traditional forms: by the post-war period, modernism had become part of art history 
• a movement towards modifying traditional beliefs in accordance with modern ideas, especially in the Roman Catholic Church in the late 19th and early 20th centuries.

http://www.angelathirlwell.co.uk/Pages/Article4.htm
For the mid-Victorians, society was on the cusp of radical change. Madox Brown analysed Victorian society in his epic picture, simply called Work, in which he raised the manual worker, the humble British navvy, to heroic status, the centre of Brown’s moral vision and of the picture. His grandson identified the way the post-war era stranded pre-war attitudes, just as Victorian social change and technology stranded the idle rich on their horses in the background of Work, and as Carlyle and Maurice, on the picture’s extreme right, looked bemused and stranded. ‘The land had not changed…’ mused Mark Tietjens. ‘There were still the deep beechwoods making groves beside the ploughlands and the rooks rising lazily as the plough came towards them.’

http://en.wikipedia.org/wiki/Work_(painting)
Composition and significance
A current day view of The Mount, Heath Street: the location used for Work The painting is structured by the increasing compression of space from right to left, as the rural relaxation on the right side is replaced by the concentrated labour in the middle and the urban crush on the far left. The workers in the centre break up the established relationship between the characters, throwing people together in new ways. Brown reproduces the common triangular structure of the social system, with the horse-riding aristocrats at the top. But they are pushed to the back, stuck and unable to progress — forced into the shade in the background, while the workers occupy the brightly lit foreground. The railings around the excavations separate the realm of productive work from that of leisure, lassitude and unproductive work. As with most Pre-Raphaelite paintings the composition minimises chiaroscuro and accummulates motifs in deliberately confusing abundance, containing numerous Hogarthian sub-episodes within the main image (a man washing windows; a dog worrying horses leading a carriage etc.). The composition is also used to dramatically crop figures and motifs which complicates the legibility of space (the hand emerging from the hole; the cropped figures behind the intellectuals' head). Carlyle's smile links the viewer in a paradoxical engagement with the re-working process depicted.

Modernism--A Working Definition

Victorian

• Modernism is a cultural movement which rebelled against Victorian mores
• Victorian culture emphasized nationalism and cultural absolutism.
• They believed in a single way of looking at the world, and in absolute and clear-cut dichotomies between right and wrong, good and bad, and hero and villain
• the world as neatly divided between "civilized" and "savage" peoples 
• "civilized" were those from industrialized nations, cash-based economies, Protestant Christian traditions, and patriarchal societies 
• "savage" were those from agrarian or hunter-gatherer tribes, barter-based economies, "pagan" or "totemistic" traditions, and matriarchal (or at least "unmanly" societies)

Modernism (1898-1945)

• Blaming Victorianism for such evils as slavery, racism, and imperialism--and later for World War I Modernists emphasized humanism over nationalism, and argued for cultural relativism.
• Argued for multiple ways of looking at the world, and blurred the Victorian dichotomies by presenting antiheroes, uncategorizable persons, and anti-art movements like Dada.
• challenged the idea that God played an active role in the world, Modernists argued that no thing or person was born for a specific use; instead, they found or made their own meaning in the world.
• Challenging the Victorian dichotomy between "civilized" and "savage", Modernists reversed the values associated with each kind of culture.
• "civilized" as greedy and warmongering (instead of being industrialized nations and cash-based economies), as hypocrites (rather than Christians), and as enemies of freedom and self-realization (instead of good patriarchs)
• "savages" the Modernists saw as being the truly civilized--responsible users of their environments, unselfish and family-oriented, generous, creative, mystical and full of wonder, and egalitarian