The Napoleonic Legacy and the Age of Jomini

The end of the Napoleonic Wars in 1815 did not mark the end of Napoleonic-era military strategy. For the next half-century, European armies continued to fight using the same formations and tactics that had dominated the battlefields of the early 19th century. Infantry marched in tight columns or lines, firing volleys in unison, while artillery blasted away at enemy formations and cavalry charged in disciplined waves. These methods were enshrined in the writings of Antoine-Henri Jomini, a Swiss officer who had served under Napoleon and became one of the most influential military theorists of his time.

Jomini’s Summary of the Art of War (1838) codified the concept of “interior lines”—the idea that an army could concentrate its forces at decisive points to achieve local superiority. This principle dominated European military thinking for decades, shaping conflicts from the South American wars of independence to the Crimean War. Meanwhile, Carl von Clausewitz’s On War (1832), though less recognized at the time, was quietly influencing Prussian strategists, including the future architect of German unification, Helmuth von Moltke.

The Industrial Revolution Transforms Warfare

The real catalyst for change came not from military theorists but from the Industrial Revolution. Between 1815 and 1860, technological advancements revolutionized European society—and warfare. The Bessemer process (1855) enabled mass production of high-quality steel, while mechanized factories churned out uniforms and equipment at unprecedented rates. But two innovations in particular would redefine military strategy: the railroad and the telegraph.

### The Rise of the Railroad

The Stockton-Darlington Railway, opened in 1825, marked the dawn of a new era. By the 1830s, visionaries like economist Friedrich List argued that a robust rail network was essential for both economic growth and national defense. Prussia’s military, however, was initially skeptical. While railroads offered logistical advantages, early studies suggested that troops could march nearly as fast as trains could carry them.

Civilian entrepreneurs, not governments, drove rail expansion. By the 1840s, Prussia’s growing rail network began to prove its worth. In 1839, the Prussian Guard used the Potsdam-Berlin line to transport 8,000 troops—a modest but symbolic step. Soon, other German states followed suit.

### The Telegraph: Instant Communication

While railroads moved troops, the telegraph moved information. Early attempts at long-distance communication, like Napoleon’s semaphore towers, were limited by visibility and weather. The invention of the electromagnetic telegraph in the 1830s—pioneered by figures like Baron Schilling and Samuel Morse—changed everything. By the 1850s, telegraph lines crisscrossed Europe, enabling near-instantaneous communication between armies and capitals.

The Turning Point: 1848 and Beyond

The Revolutions of 1848 were a watershed moment. Prussia’s swift suppression of uprisings across Germany owed much to railroads and telegraphs. Troops could be rushed to trouble spots before rebellions gained momentum, while telegraphs allowed commanders to coordinate in real time. Revolutionaries, recognizing the threat, sabotaged rail lines—but it was too late. The age of industrial warfare had arrived.

### The Humiliation of Olmütz (1850)

Prussia’s next test came in 1850, during a confrontation with Austria. The mobilization was a disaster: horses and riders were sent to different locations, supplies went missing, and entire battalions failed to arrive. Austria, by contrast, executed a flawless mobilization, forcing Prussia into a humiliating retreat at the Convention of Olmütz.

The debacle spurred reforms. Helmuth von Moltke, appointed Chief of Staff in 1858, worked closely with Commerce Minister August von der Heydt to overhaul Prussia’s rail system. Specialized rail cars were designed for troop transport, and military liaisons were stationed at key rail hubs.

### The Lessons of 1859

The Second Italian War of Independence (1859) further underscored railroads’ strategic value. France’s rapid deployment of troops to Lombardy via rail secured victory over Austria. Prussia, hesitant to commit, bungled its own mobilization—trains were diverted, and delays proved costly. Moltke, frustrated, pushed for greater coordination between military and rail planners.

The Legacy: Railways, Telegraphs, and Modern War

By the 1860s, Prussia had learned its lessons. The reforms of Moltke and von der Heydt laid the groundwork for the lightning-fast mobilizations of the Austro-Prussian (1866) and Franco-Prussian (1870-71) Wars. Railways and telegraphs didn’t just change how armies moved—they changed how wars were won.

The 19th century’s military revolution was not just about technology but about adaptation. Nations that embraced railroads and telegraphs gained a decisive edge. Those that clung to Napoleonic tactics, like Austria in 1866, found themselves outmaneuvered and outgunned. The lessons of this era still resonate today, as modern militaries grapple with the implications of AI, cyber warfare, and drone technology.

In the end, the story of railroads and telegraphs is a story of how innovation reshapes power—and how those who fail to adapt are left behind.