GRRM seems to have been responsible for (or maybe he is simply the highest profile example of) a wave of alternating multi-point of view fantasy novels.
When you think of it, it doesn't have very deep roots. LOTR eventually splits into different tracks to follow the Company after the end of the first volume, but until that point it is almost entirely from Frodo's point of view (with the exception of most of the first chapter, a couple of dreams in Bombadil's house, a Fatty Bolger vignette, and a small scene in Bree from Merry's point of view). Eddison sticks with Garion for most of his Belgariad and Malloreon, and even Jordan's sprawling narrative begins with a focus on Rand.
There are pre-fantasy examples: the obvious example is Tom Clancy, who moves rapidly away from focussing on Jack Ryan to multiple plot tracks following the development of every side of a plot. One of the reasons this works is because the typical reader has already developed enough identification with Ryan, from the first few novels which had a narrower focus, to stick with the narrative through switches in viewpoint. (What Clancy gains from it is the illusion of realism, as he shows all the steps building towards a titanic event - the nuclear bombing of an American city, or the elimination of the American government almost in toto.) And Ulysses is notoriously multi viewpoint, but as it is an advertisement for how a master can break every rule in the book successfully, we may not want to consider it.
A really good author, of course, can generate interest in a few paragraphs, and encourage us to trust him or her on a switch to a new viewpoint in a new place; and a true omniscient narratorial technique relies little, if at all, on the reader's identification with a character. On the other hand, there's also a special kind of novelistic discipline in limiting what the reader knows to what a single character knows, and only displaying it gradually as the viewpoint character learns more. The classic détective story is built on thus foundation.
However, it comes with a heightened potential for the Eight Deadly Words. I confess that it is only the testimony of others who say that there's a payoff waiting that keeps me slowly plugging through John Gwynne's Malice, especially as he also insists on combining the technique with beginning at the beginning and showing the hero's bildungsroman in excruciating detail. Brian Staveley is better - he has only three viewpoints, his characters are more interesting, and he begins with a crisis, even if not quite in medias res.
There is one area where shifting viewpoints can be a significant narrative plus. In cases where there's already tension, abandoning one viewpoint for another can set up a terrific coup de théâtre on reintegrating the former thread. Tolkien does this twice in telling of the battle in front of Minas Tirith, once with "Rohan had come at last", and once with the black ships, and repeats the trick, again, with the battle before the Black Gate being suspended for several chapters as Frodo and Sam make their way through Mordor.
Another very recent example is Miles (Christian) Cameron's The Fall of Dragons, the fifth (and last) book in the Red Knight series, which is an effectively crafted payoff to an already very good four-volume setup.
As always in this series, the military aspects have the ring of realism, the characters are three-dimensional and clearly distinguished, and the world-building is effective.
By setting this volume up so that every thread is critical in a finely arranged set of dominoes -- failure in any one battle, delay in any one march, would be a serious problem, and there is a strict timeline to boot -- and by having already established a grounding in the core viewpoint characters, the effect Cameron achieves is one of heightening tension whenever he shifts from viewpoint to viewpoint. And this works, in turn, because it's believable that such a tightly-connected plan would be in place, because (in turn) it's a desperate roll of the dice against an overwhelmingly superior foe, so that the usual caveat against creating frangible plans in military (or, for that matter, any other) matters cedes place to sheer desperate necessity.
It's also helped by Cameron's willingness to sacrifice viewpoint characters, so even the degree of "happiness" of the ending can't be clearly anticipated. You can't assume that anyone will necessarily get through the narrative alive. It's not grimdark - there's too much virtue in the best of his protagonists for that - but it's gritty and the costs of war are realistic.
Thematically, a venerable thesis about good and evil plays out, one which works its way through Tolkien as well. The Red Knight's side, with independently cooperating leaders and motivated soldiers, can respond effectively and with initiative when small things go wrong, whereas Ash's side's overwhelming of wills and individuality (displayed also in a somewhat different ways for the Odine) sets up conditions where setbacks can happen more easily and unravel more when they happen. Evil fails in part because of its lack of imagination, an inability to understand the motivations of its foes and therefore is unable to anticipate what they will do; it also favours a highly centralized command and control model (with entities like Ash who have near-godlike powers, literal mind control from a distance) which is rigid and inflexible. This thesis is more clearly expressed because we can actually see the process by which Ash works, as his viewpoint occasionally is given its place in the sun; by contrast, Sauron is always a shadow in the background.
Overall, this is a satisfying conclusion to a well-written series, and a nice demonstration of how a multi-pov technique can be effectively used.
When you think of it, it doesn't have very deep roots. LOTR eventually splits into different tracks to follow the Company after the end of the first volume, but until that point it is almost entirely from Frodo's point of view (with the exception of most of the first chapter, a couple of dreams in Bombadil's house, a Fatty Bolger vignette, and a small scene in Bree from Merry's point of view). Eddison sticks with Garion for most of his Belgariad and Malloreon, and even Jordan's sprawling narrative begins with a focus on Rand.
There are pre-fantasy examples: the obvious example is Tom Clancy, who moves rapidly away from focussing on Jack Ryan to multiple plot tracks following the development of every side of a plot. One of the reasons this works is because the typical reader has already developed enough identification with Ryan, from the first few novels which had a narrower focus, to stick with the narrative through switches in viewpoint. (What Clancy gains from it is the illusion of realism, as he shows all the steps building towards a titanic event - the nuclear bombing of an American city, or the elimination of the American government almost in toto.) And Ulysses is notoriously multi viewpoint, but as it is an advertisement for how a master can break every rule in the book successfully, we may not want to consider it.
A really good author, of course, can generate interest in a few paragraphs, and encourage us to trust him or her on a switch to a new viewpoint in a new place; and a true omniscient narratorial technique relies little, if at all, on the reader's identification with a character. On the other hand, there's also a special kind of novelistic discipline in limiting what the reader knows to what a single character knows, and only displaying it gradually as the viewpoint character learns more. The classic détective story is built on thus foundation.
However, it comes with a heightened potential for the Eight Deadly Words. I confess that it is only the testimony of others who say that there's a payoff waiting that keeps me slowly plugging through John Gwynne's Malice, especially as he also insists on combining the technique with beginning at the beginning and showing the hero's bildungsroman in excruciating detail. Brian Staveley is better - he has only three viewpoints, his characters are more interesting, and he begins with a crisis, even if not quite in medias res.
There is one area where shifting viewpoints can be a significant narrative plus. In cases where there's already tension, abandoning one viewpoint for another can set up a terrific coup de théâtre on reintegrating the former thread. Tolkien does this twice in telling of the battle in front of Minas Tirith, once with "Rohan had come at last", and once with the black ships, and repeats the trick, again, with the battle before the Black Gate being suspended for several chapters as Frodo and Sam make their way through Mordor.
Another very recent example is Miles (Christian) Cameron's The Fall of Dragons, the fifth (and last) book in the Red Knight series, which is an effectively crafted payoff to an already very good four-volume setup.
As always in this series, the military aspects have the ring of realism, the characters are three-dimensional and clearly distinguished, and the world-building is effective.
By setting this volume up so that every thread is critical in a finely arranged set of dominoes -- failure in any one battle, delay in any one march, would be a serious problem, and there is a strict timeline to boot -- and by having already established a grounding in the core viewpoint characters, the effect Cameron achieves is one of heightening tension whenever he shifts from viewpoint to viewpoint. And this works, in turn, because it's believable that such a tightly-connected plan would be in place, because (in turn) it's a desperate roll of the dice against an overwhelmingly superior foe, so that the usual caveat against creating frangible plans in military (or, for that matter, any other) matters cedes place to sheer desperate necessity.
It's also helped by Cameron's willingness to sacrifice viewpoint characters, so even the degree of "happiness" of the ending can't be clearly anticipated. You can't assume that anyone will necessarily get through the narrative alive. It's not grimdark - there's too much virtue in the best of his protagonists for that - but it's gritty and the costs of war are realistic.
Thematically, a venerable thesis about good and evil plays out, one which works its way through Tolkien as well. The Red Knight's side, with independently cooperating leaders and motivated soldiers, can respond effectively and with initiative when small things go wrong, whereas Ash's side's overwhelming of wills and individuality (displayed also in a somewhat different ways for the Odine) sets up conditions where setbacks can happen more easily and unravel more when they happen. Evil fails in part because of its lack of imagination, an inability to understand the motivations of its foes and therefore is unable to anticipate what they will do; it also favours a highly centralized command and control model (with entities like Ash who have near-godlike powers, literal mind control from a distance) which is rigid and inflexible. This thesis is more clearly expressed because we can actually see the process by which Ash works, as his viewpoint occasionally is given its place in the sun; by contrast, Sauron is always a shadow in the background.
Overall, this is a satisfying conclusion to a well-written series, and a nice demonstration of how a multi-pov technique can be effectively used.