The subjects this film deals with are ugly, but the whole thing is done in a beautiful way.
Subjects dealt with are racism, poverty and the reasons why.
The way Griffith deals with these subjects is the contrasts settings. Look at the room above the Chinaman's shop: opulent, festooned with the finest oriental silk. Compare that with the stark squalor of the abode of Lucy and her bruiser of a father. Then there is the education and sophistication of the orientals compared to the simplistic, ill-thought-out racial prejudice of Battling and his cronies.
I also enjoyed the boxing match. Very realistic - not the fantastic nonsense of your Rocky-type bout where a man all but beaten to a jelly suddenly pulls some heavy punches from nowhere and wins the fight.
The acting, as has been mentioned elsewhere, is terrific from all three of the principal characters. Also, their characters are well-drawn. Even Battling Burrows - complete with cauliflower ear - is more than a mere heavy: he boxes for a living, he drinks, he lives in a slum with few worldly possessions. Why?
I find it hard to believe that the films they make nowadays are nowhere near as good as this. Whatever happened to progress?
This film spawned the famous song "Limehouse Blues."