The Wind That Shakes The Barley takes its title from a typically sentimental Irish ballad by Robert Dwyer Joyce about the 1798 Irish Rebellion. This necessitates a couple of warnings for prospective viewers: one, that despite the amount of sheer historical connotations packed into the title, appreciation of Ken Loach's latest film does not require a particularly adept command of history; and two, that the title's eloquence is equally misleading. Here, history isn't the province of speech-makers: as in so much of Loach's work, history is decided by committees prone to inarticulate, factional squabbling.

Ostensibly focusing on one Damien O'Donovan (Cillian Murphy, providing a little marketable star power), the film often loses itself in a cluster of young, outraged Irishmen joining in the 1920s IRA rebellion. Political sympathies don't even enter into one's response to the film; specific in its historical outline but fictional in its characters, this is a study in how movements are made and unmade, not necessarily a briefing on the terrorism perpetrated by the British (although audience members still inexplicably in favor of the occupation of Ireland might be somewhat offended).

Damien, a prospective doctor on his way to London, at first argues against the rebellion; when a lad is beaten to death for refusing to give his name to the Black & Tan forces brutally representing Her Majesty, Damien questions whether that's martyrdom or stupidity. But seeing another beating on the train platform changes his mind, and shortly thereafter Damien joins the corps, marching through the hills on shoddily-run guerrilla training exercises. Despite scant resources and lack of pro experience, the IRA begins making waves; the point when concessions can be won, however, is precisely the point of disintegration. Adept as the rebels are at shooting surprised officers, they're considerably less skilled at diplomatic negotiations, meaning that the hard-won momentum of the rebellion might be for naught.

For the majority of its running time, The Wind That Shakes The Barley cloaks its structure in constant inter-factional squabbling. The troops get better at running military exercises in the hills, but once they wrest control of a town they're hopeless. In a key scene, the ad hoc IRA court has its authority rejected when it tries to issue a fine on a businessman who also provides financing for their weapons purchases, but systematic justice is impossible to pursue when pragmatism and revenge enter the picture. The stakes and retaliatory actions keep escalating, yet the coherence of the IRA's agenda never improves.

The Wind That Shakes The Barley imagines history as entropy and dumb luck. None of the characters are actually historically recorded, but they're plausible fictional counterparts to numerous similar Irish and British characters, which is kind of the point. Loach has always been an activist filmmaker, to extents that are more obvious than they are here; his portrait of the sadistic, occupying British seems to court comparisons with the current occupation, even as it coyly demands to be taken on its own terms. It's a movie that wants to suggest analogues without really committing to them.

Fortunately, its own terms are reasonably riveting -- cleanly directed, strikingly violent, resolutely non-sentimental -- until the last 20 minutes, when the cycle of spiraling violence has finally become actively repetitive, but the movie must continue until its leading man/designated-star-power-provider’s character arc has acquired the kind of resolution denied to the story as a whole. It's an understandable decision for financing reasons, but it takes the movie down a notch; the requirements of protagonist-based narrative (which, at heart, this film is not) and the inconclusive nature of the historical subject matter clash badly. Still, it's easily the best movie the subject has seen this side of the millennium, and viewers who feel bold enough to make their own mental cut of the wobbly ending by walking out early may be especially rewarded.