AJ Black’s review published on Letterboxd :
As presented by the custodian of New York based moviemaking, Martin Scorsese, Gangs of New York is a frequently fascinating look into a hitherto under realised period of the city's traumatic history, and that of America itself in general. Set between the 1840's-60's, Scorsese's film depicts the battle to establish democracy in what would become the Big Apple, writ small as something of a microcosm for the burgeoning United States in general, through the prism of a violent gang culture that battled for supremacy in the shadow of a difficult Civil War at its height and the institution of the first signs of conscription on a populous who didn't want to fight for their country. It becomes a majestic canvas of history for Scorsese to paint a story of honour, of vengeance, of fathers & sons, yet one that never quite strikes as powerful an emotional or visceral chord as this most talented of auteurs is capable of. To many other directors, this would be their masterpiece. For Marty, it's mid-range.
That said, it's damn hard not to be impressed by Gangs of New York in many ways. Chiefly the production design which is truly outstanding from top to bottom - Dante Ferretti building in the vast Cinecitta Studios in Rome several miles of a Manhattan that has been long lost to history in the real world, and it's an immersive construction that deserved awards; such a sandbox allows Scorsese to create a vivid picture where you truly feel part of an alien historical world, a New York totally unlike anything previously committed to celluloid & so far removed from the metropolis we know now. This is a proto-city made up of fiefs, communities, small kingdoms & tribes all fuelled by racial tensions, belief systems & often quarrels with God; it's telling that Liam Neeson's devout priest & gang leader is the trigger for Leonardo DiCaprio's Amsterdam burning for revenge as he becomes ensconced inside the gang that killed him. Scorsese evokes this period masterfully, from costume design to remarkable period detail, capturing the lawlessness of the culture in tandem with a corrupt political system epitomised by Jim Broadbent's amiably venal Tweed, who in lieu of the democracy war & strife would force upon the city appeased the gangs. It's all vivid historical portraiture on screen, and must surely represent a largely accurate portrayal of the period.
The reason why Gangs of New York isn't a Scorsese great, however, is that you're left hugely impressed without truly feeling the power of any of it - thanks to a meandering narrative & a script that doesn't give a hugely talented cast chance to do their best work. DiCaprio is solid, negotiating a wobbly (though intentionally wobbly) accent, but that burning intensity he's displayed in other movies isn't quite there - he's good but he's done better; Daniel Day-Lewis of course again got an Academy Award nomination for Bill the Butcher, and it's fair to say he's one of the film's standouts - a brutish, racist murderer brimming with bile, and when Day-Lewis gets chance to let him off the hook he's typically mesmerising; the film is often firing on greater cylinders when he's on screen. Cameron Diaz too is a lot better than usual as fiesty wench Jenny, displaying a real backbone of commitment in a tricky role - it's a shame she doesn't aspire to more such projects that tap the talent she clearly does have. Yet for all the decent performances, Scorsese just doesn't give this quite enough vicious bite - it's very talky often, the pacing drags after a vibrant opening, and though he delivers a strikingly violent & vivid climax, we've spent too long in construction for it to impact like it should. You should care more in the inevitable confrontation between Amsterdam & Bill than you frankly do.
Gangs of New York therefore isn't Martin Scorsese's greater work, yet that's not to say it shouldn't be seen; it's an incredibly fascinating picture with production design that is truly second to none, recreating the often uncharted 19th century period with incredible detail in a way many films can never reach. Scorsese directs too with the scope you'd expect, but while he's working with a deeply talented ensemble, sadly they're working from a script that lacks enough punch & a story that wanders when it should be hitting you between the eyes more often than it does. At the very least, Gangs of New York will teach you a fascinating visual lesson in how one America's greatest cities was born.