It must chafe professional historians that one of the most important history books ever published was written by an amateur. A smart amateur, of course, but essentially a mildly incompetent American sea captain whose family connections helped wrangle him a lectureship on tactics at the Naval War College in 1885, despite the fact that he had only an undergraduate degree. In preparation for his lectures, he buried himself in the library and, working almost entirely from secondary sources, he emerged in 1890 with a book that would shape the next half century of warfare around the world.

His name, of course, was Captain Mahan—Alfred Thayer Mahan—and his book was called The Influence of Sea Power upon History, 1660–1783. The son of a legendary professor at West Point, Mahan would extend his study of sea power through more books, and only in the final volume of his first historical reflections did he turn directly to the life of Lord Nelson. But to read any of Mahan’s writing is to realize that he always had Horatio Nelson somewhere in mind. And why not? Everyone who thinks about the sea must eventually face up to Nelson and what he means. The title of Mahan’s 1897 biography, The Life of Nelson: The Embodiment of the Sea Power of Great Britain, is wildly extravagant and yet it is somehow entirely appropriate.

You can begin to see why if you read about the captains who served under Nelson at one or more of his three great victories: the Battle of the Nile in 1798, the Battle of Copenhagen in 1801, and the Battle of Trafalgar in 1805. A beautiful new volume edited by Peter Hore, a retired British naval captain, allows you to do just that. In Nelson’s Band of Brothers: Lives and Memorials, Hore has collected brief essays on 80 seamen by a set of international historians (some of them descendants of Nelson’s followers). Each section of the book begins with an account of one of the battles before taking up the lives of the individuals who fought it.

What emerges from these mini-biographies is the impact of Nelson on the professionalism that the British navy managed to establish in the wars against the French.

In truth, Nelson may not have been the best fighting captain of his time. The exploits of Lord Cochrane while commanding the Speedy, the Pallas, and the Imperieuse from 1800 to 1809 are almost too prodigal for anything but fiction—a fact realized by Napoleonic War novelists from C.S. Forester (with his Captain Horatio Hornblower) to Patrick O’Brien (with his Captain Jack Aubrey). Frederick Marryat, the first writer of adventure stories about the British navy, actually served under Cochrane on the Imperieuse in 1806, and he needed no exaggeration to tell the tale of Cochrane’s battles against the French.

Neither was Nelson necessarily the best pure sailor of his time. William Bligh had been an ordinary seaman who worked his way up to command, and the journey he made to Timor in 1789 was an unrivaled piece of sailing: over 4,000 miles in an open boat after being set adrift by the HMS Bounty mutineers. One doubts that Nelson—or many other officers, however skillful—could have made the voyage.

But it’s by the measure of Cochrane and Bligh that Nelson’s greatest talents become evident. Nelson was a brilliant naval officer. Even if he wasn’t quite as insane a dynamo as Cochrane in single-ship combat, Nelson could still perceive the course of a battle like no other. So, for example, during his first major fight as a senior commander—at Cape St. Vincent, where he left the line to break his Spanish adversaries’ attempt to reunite their fleet—he alone managed to see the shape of the confrontation as it unfolded. At Copenhagen, his famous refusal of Hyde Parker’s order to retreat (which he signaled by putting his telescope to his blind eye) came from his realization that the turning point had actually been passed and the battle’s momentum had shifted away from the Danes, even though it looked as though the British ships had stalled in their assault.

Similarly, if he wasn’t the master sailor of the entire fleet, he nonetheless proved his ship-handling as early as 1780, when he took the Hinchinbrook far up the San Juan River to capture a Spanish fort in Nicaragua. Such men as Cochrane and Bligh were superb at what they did best, but Nelson was nearly as good at those things and better at everything else—especially at managing people.

Cochrane—whether fighting for the British or the South American republics, whether in the navy or in the British parliament—invariably managed to alienate those around him, quarreling with his superiors, inferiors, and equals alike. Bligh served under Nelson at Copenhagen with distinction (choosing, at a key moment, to disseminate to the fleet Nelson’s signal to continue the fight rather than Parker’s withdrawal order). But his brutality and insensitivity left him the victim of the Bounty mutiny in 1789—and victim of the 1808 Rum Rebellion, when his endless wrangling led the military and local citizens to depose him as governor of New South Wales.

Nelson, in contrast, left behind a band of brothers, the officers who would set the tone of the British Navy for the next hundred years. And that hundred years, it’s worth remembering, form the era in which much of the world was dominated by Great Britain, primarily because of its sea power.

A professional seaman, editor Hore is drawn to the professionalism that Nelson established, his image constantly in British officers’ minds. An easy example—highlighted by Joseph F. Callo (biographer of another famous sailor, John Paul Jones)—is Thomas Foley, one of Nelson’s followers, who captained HMS Goliath at the Battle of the Nile. Thirteen French ships were anchored in a row along the shore of Aboukir Bay after escorting the transports that had carried Napoleon’s army to Egypt. After months of searching up and down the Mediterranean for the missing French, Nelson was determined to start the battle immediately, even though it was already late afternoon when he found them.

Approaching from the west, Captain Foley judged that the gap between the enemy ships and the shoals might be larger than the French had intended. So he left the British line to swing to the landward side of the French—and when he didn’t run aground, four of the 13 British captains followed him, while the other British ships continued along the seaward side.

The French ships, attacked on both sides, were overwhelmed one by one until Nelson had achieved his most complete victory: Starting with even forces, the British lost none of their vessels, while the French had two of theirs destroyed and nine captured, with the killed, wounded, or captured running as high as 81 percent of the French sailors.

And the key to it, Foley’s risky turn to landward, began with his confidence that Nelson would protect him from any later bureaucratic punishment for his boldness. With the blockade system bottling the Continental fleets in harbor, the British crews and officers had months more of sea time to train and practice than their Spanish and French counterparts, and that extra time consistently showed in the course of battles. But the British also had a tone of competence, trust, and nerve—a tone that Nelson’s band of brothers had everything to do with establishing.

Nelson may have been vain and hungry for praise. (“Before this time tomorrow I shall have gained a peerage or Westminster Abbey,” he told his captains before the Nile­—and he was more or less accurate.) Then, too, he either foolishly seduced, or was foolishly seduced by, Lady Hamilton, and he lingered in port to be with her. But he had a genius for naval warfare—a key part of which was his ability to form men to a high standard.

It’s at this point, however, that Hore’s emphasis on naval professionalism feels insufficient. Good as Nelson’s Band of Brothers is, weighing the admiral’s importance with exactness requires something more, something like the extravagance of Mahan’s work on the emblems of history—for Nelson really was the embodiment of modern sea power.

To look back at Mahan’s Influence of Sea Power upon History now is to notice how the implementation of its theories shaped military practice in the decades that followed its 1890 publication. The book fueled the giantism that turned battleships into dreadnaughts, for example, along with the near-bankrupting of the European powers in the naval arms race before the First World War and the dawn of Japan as an international force through the Japanese navy’s triumphs in the Russo-Japanese War.

Mahan’s work shaped even the unraveling of his theories. The naval rush into submarines and aircraft, from the First World War through the Cold War, came at least partially from a realization that Mahan had been right: Control of the sea’s surface equals strategic advantage in any large war of nations, and the only ways to overcome it are from beneath the surface or above. Even the rise of asymmetrical warfare after the Second World War—in all the guerrilla battles and terrorism that aimed at ending the colonial empires of the Western powers—can be interpreted as strategies designed to make an end run around the iron logic of Mahan’s vision of decisive naval action as the key to war.

Lord Nelson would have wept at the sight of the Royal Navy inching its way through the Battle of Jutland in 1916. But the British leader, Admiral Jellicoe, had at least one excuse for his caution: As the only large-scale clash of warships in the First World War, Jutland was the one occasion in which Britain could have lost the war in a single day. The battle was fought around Mahan’s idea that sea power eventually determines land power.

Although Mahan was keenly aware of how genius (or idiocy) in commanders can turn the tide of battle, the American writer was not an uncritical proponent of Thomas Carlyle’s theory of great men as the engines of history. Much as he admired Horatio Nelson, Mahan refused to see the British admiral as a demi-god. He interpreted Nelson instead as an embodiment, an avatar: the emblematic figure whose genius allowed him to show the effect of sea power when delivered forcefully and precisely. The British Empire was at its root a naval empire, and it was made possible by a kind of naval determinism that kept other nations from acting as fully on the world’s stage. For Mahan, Lord Nelson was not a person so much as a personification, the living realization of a historical law.

From a certain angle, it can all seem a little much, a little overdrawn. But, then, a great deal of what the British achieved at sea during the Napoleonic wars seems a little much, from the exploits of Cochrane to the victories of Nelson himself. In Nelson’s Band of Brothers, Peter Hore gives us part of the story, and maybe the best part. Still, Captain Mahan’s account shouldn’t be dismissed as antiquated, for Mahan, too, caught a real part of the story. History set Nelson up atop a column in Trafalgar Square for very good reason.