What are some characteristics of the Romantic movement and who are its major representatives?

Romanticism in Music was an extension of the Classical era
that it followed. Essentially, it was the increase in emotional content and use of "tone
colours" and the decrease in strict form and structure. There was also an increase in
nationalism in music.

Composers started to write
orchestral music that was programatic, ie, music that tells a story, describes an idea
or an emotion. To say that the Romantic Era and the Classical Era were completely
different eras however is wrong. All of the same characteristics were there.
Orchestration was similar, as was the make up of the orchestra itself, just the
orchestras used by romantic composers was larger.

One main
difference was the increased use of chromaticism in Romantic music and as the era
progressed this shifted entirely from the Chord I, IV, V progression of the Baroque and
Classical to the almost free form chord progessions of the late 19th
century.

As for major representatives, Beethoven was one of
the first and his nine symphonies beautifully show the transition from Classical to
Romantic styles of writing. Chopin and Liszt for the romantic piano solos, Wagner for
opera, Berlioz and Bartok for Orchestration. Tchaicovsky was in there for piano,
romantic ballet, orchestration. Debussy and Ravel for impressionism and some of the late
romantic composers such as Rachmaninov and Holst wrote some of the most beautiful music
on earth (my opinion).

Hopefully that gives you some places
to start looking further. Program music, nationalism and Impressionism were the 3 major
movements of the Romantic era so in any assignment, I'd start looking
there.