November 6th is celebrated in Sweden, Estonia and Finland as Gustavus Adolphus Day, coinciding with the anniversary of his death at the Battle of Lützen in 1632. King of Sweden from 1611 to 1632, Gustavus Adolphus made Sweden a great power in the 17th century. He was something of a one-man military revolution, installing into his superbly-trained army principles that still hold true today, including concentration of fire, mobile field artillery, combined arms, and victory through manoeuvre. His intervention in the Thirty Years’ War ensured that Protestant northern Germany would never be retaken by allied Catholic forces and preserved the Swedish Empire for long after his death, achievements which justly earned him the sobriquet “The Lion of the North”.
Born in 1594 to Charles IX, Gustavus inherited a nation that was staunchly Protestant and also under siege from Poland. Overthrown by Charles in 1599, his Catholic cousin Sigismund had fled to Poland and agitated to regain his throne. Upon assuming the throne in 1611, Gustavus had to deal with a naval invasion of Stockholm by the Danes, which he dealt with by using a rapid forced march, followed by the conscription of every man in the city to resist the assault. Disturbed by the size of the opposition, King Christian IX withdrew and concluded peace two years later. In 1614, Gustavus invaded the coast of Sweden’s largest rival, Russia, and in 1617 successfully concluded a peace that gave Sweden control of all of Russia’s Baltic coast, and by extension, all of its overseas trade.
In 1617, with Sigismund courting Swedish nobles to restore him to the throne, Gustavus began a series of conflicts with Poland that lasted until 1629. Poland ceded the larger part of Livonia and the important port of Riga. The threat of Sigismund was removed, and the wars had been the proving ground for Gustavus’ new military system.
Gustavus made two key decisions in these wars that would serve him well. Firstly, he disdained sieges and understood that an intact army that ceded a city was more important than one trapped by a besieging enemy. Secondly, he displayed remarkable humanity to civilians. His troops were subject to strict discipline: there was to be no pillaging, and all forage was to be paid for. Deviation from these orders merited a death sentence.
The European way of war in the 17th century owed much to the Spanish. The primary weapons were the pike and the firelock, the latter being split into the arquebus and heavier but more powerful musket. Firelocks provided enormous offensive power, but even a good musketeer could take ninety seconds to load his weapon. The Spanish therefore developed the countermarch: gunners would line up in files up to thirty men deep. The first man would fire his weapon and retreat to the back of the file to reload, with the second man taking his place, and so on. The gunners were arranged in “sleeves” around a deep formation of pikemen. This block of men armed with pikes some fourteen feet long provided a refuge for the gunners when the enemy’s cavalry attacked, keeping the horses at bay, and delivered the final push against enemy formations once they had been disordered by musket fire. This combined arms formation of pike and shot was known as the tercio and numbered between one thousand and three thousand men.
This also meant that a well-timed cavalry charge could no longer win the day on the battlefield. Tercios were all-but unbreakable. Instead, cavalrymen rode in small, dense columns several ranks deep, armed with wheellock pistols. When they approached the enemy formation, the front rank would fire its pistols, and then rapidly wheel away down the length of the column, making room for the next rank to fire, a tactic known as the caracole. This could easily be broken by a counter-charge and Gustavus seems to have regarded the tactic as useless.
Caught up in the Eighty Years’ War against the Spanish, the Dutch were the first to look for ways to break the tercio. Maurice of Nassau was the first to realise that the huge, slow tercio made for a large target. Thus he reduced the size of his formations from two thousand to six hundred men, and arranged them no more than ten ranks deep. In doing so he brought a vastly greater number of guns to bear on a longer front, and by having two ranks fire at the same time before countermarching, he increased the power of his volleys. These smaller battalions were much more mobile than the huge, unwieldy Spanish tercios. Maurice also standardised the calibres and manufacture of artillery, as well as improving drill, pay and supply to his armies.
Maurice’s battles at Turnhout in 1597 and Neiuwpoort in 1600 were victories, but hardly overwhelming ones. Maurice’s innovations clearly had merit, but more work was still to be done. Gustavus built on this foundation. His squadrons numbered four hundred men, split equally between pike and musket, and arranged only six men deep. Gustavus also dramatically expanded use of the paper cartridge for muskets, getting rid of the powder horn and so dramatically shortening the reloading procedure. Sweden had difficulty in finding material to make match cord for firelocks, so Gustavus replaced matchlock muskets with the more reliable and easier to use snaplock mechanism, which was much less likely to be rendered useless by bad weather. By manufacturing a lighter musket, the Swedes removed the need for a rest, reducing reloading time and so increasing rate of fire. The two-rank volley developed by the Dutch was increased to three ranks. When Gustavus’ men countermarched, rather than move back through the formation, they stood fast while the next ranks moved past them to fire, creating almost a rolling barrage.
In addition to this enormous increase in infantry firepower, Gustavus was also the first to develop lightweight field artillery. Until him, cannon had been extremely large and heavy, and so were generally kept in fixed positions on the battlefield. Gustavus’ guns were cast in standardised calibres and weights of 24-, 12-, and 3- (later increased to 4-) pounders. The smallest guns were light enough to be drawn by one horse or three men, and so could provide mobile fire support on the battlefield. As with the musketeers, gunpowder cartridges dramatically simplified loading and increased rate of fire. The Swedes under Gustavus had the finest artillery in Europe and arguably the modern role of artillery on the battlefield began with them.
Gustavus also restored cavalry as the decisive offensive arm. Every cavalry unit had dismounted musketeers attached, which would deliver a massed volley against the enemy before the cavalry charged with sabres. 3-pounder guns were also attached to the cavalry to provide support. Gustavus’ cavalrymen would be essential in the battles of Breitenfeld and Lützen.
Perhaps his most enduring innovation, however, is the organisational culture Gustavus brought to his army. Using the conscription system brought in by his grandfather, he built an army of over one million men that was well-supported by an efficient tax base and supply system at home. As stated above, Gustavus kept his soldiers under strict orders not to abuse civilians, and he used companies of mercenaries only as a last resort, and even then forced them to work within the same framework as the rest of his army. Prior to then, mercenaries had been too independent to form effective fighting forces; their movements controlled not by strategy but instead a search for territories that had not already been plundered for sustenance. In addition, his men were treated without favouritism and were extensively cross-trained. This came in exceptionally useful at the Battle of Breitenfeld in September 1631.
Breitenfeld was the great battlefield test of Gustavus’ system, fought against none other than the superb field marshal of the Catholic League, Count Tilly. He brought 21,400 infantry, 9,900 cavalry, and 26 guns to the field, against Gustavus’ 14,742 infantry, 8,064 horse, and 52 guns. The Swedes were reinforced by a Saxon army of 12,100 infantry under John George. However, the Saxons were inexperienced and were wedded to the tercio formation, and would not prove particularly useful on the battlefield.
Neither the Swedes nor the Imperials had a particular terrain advantage; indeed, Gustavus’ rear was covered by a stream, narrowing his range of options if he had to retreat. The battle began around noon with an artillery duel, and the superior numbers and skill of Gustavus’ artillery wrecked havoc on the densely-packed Imperial tercios. The deep blocks of men were huge targets.
The Imperial cavalry launched their first assault at around 14:00, followed closely by the infantry, against the Saxons on Gustavus’ left. It is a testament to Tilly’s skill that he successfully marched his unwieldy tercios in oblique order against the Saxons. Already terrorised by the two-hour bombardment, the green Saxon troops broke and ran, and Tilly prepared to roll up the Saxon line. However, the Swedish left under General Horn swiftly reordered their more mobile brigades and refused the flank. Swedish musketeers and artillery were able to pour a withering fire into the tercios as they struggled to turn to face them, and it took until 16:00 before Tilly was able to continue the attack.
On the Swedish right, the Imperials had no similar success. Cavalry under Pappenheim were repulsed by Gustavus’ mixed cavalry-musketeer units. Pappenheim rode further west in an effort to turn the flank, only to charge into a second refused flank under General Baner. Seven attacks failed, shot to pieces by Swedish musketry, and Pappenheim retreated at 16:00, just as Tilly had reordered his tercios to attack the Swedish right.
Horn went on the offensive against Tilly and threw the Imperial ranks into disorder. Meanwhile, Baner’s left wing advanced and swung east to occupy the Imperial’s starting positions, seizing their guns. Gustavus led the cavalry charge personally. Famously proclaiming; “The Lord God is my armour!” he wore only a leather jerkin to protect him. The decision was more physical than spiritual, as he had been injured in the shoulder during the Polish-Swedish wars and so could not wear iron armour.
Here the army’s cross-training came into play as the infantry seized the Imperial guns and turned them on Tilly’s tercios. The Imperials endured hours of punishment before breaking and retreating, and the Swedish pursuit was swift. Tilly himself was wounded. 7,600 Imperials were dead; 6,000 were taken prisoner. Another 3,000 surrendered to next day at Leipzig. All 26 guns were lost as well as 120 regimental colours. Swedish losses were 2,100, while the Saxons lost 3,000 men.
The Swedish army, with its emphasis on professionalism in both training and spirit, and victory through firepower and aggressive manoeuvre by both cavalry and infantry, had won the day. Gustavus’ new concept of combined arms and linear tactics had shown that the days of mass- and casualty-intensive tercio tactics and indecisive caracoles, were over. At the Battle of Lützen the next year, Gustavus’ faced an Imperial army that had adopted his own linear system. It is a testament to the success of his tactics that his opponents adopted them so rapidly.
The Battle of Lützen was fought on this day in 1632. A road separating their two positions, the Swedes and Imperials drew up, 19,000 men to 16,770. Gustavus had a slight edge in numbers, but for every minute he delayed, 10,000 Imperial reinforcements marched closer. Fog shrouded the battlefield until it lifted at 11:00, and only then could Gustavus begin the attack. His artillery pounded the Imperial centre, and Gustavus personally led his cavalry against the Imperial left.
The Imperial commander, Albrecht von Wallenstein, had anticipated the movement, however, and had concealed musketeers in drainage ditches along the side of the road across the battlefield. The Swedes received fire from them almost immediately and quickly lost the initiative. The follow-up infantry managed to clear the ditches, but the shock of a cavalry charge was lost. Nevertheless, the Swedes managed to make steady headway against them Imperial left.
On the Swedish left near Lützen, shrouded in smoke after Wallenstein had ordered the town burned, a ghastly attritional slog ensued. Meanwhile, 2,300 Imperial cavalry arrived under Pappenheim, and the legendarily-impulsive commander gathered some brigades from the Imperial centre and counter-charged Gustavus. The Swedes swiftly improvised a defensive line and unleashed a wave of fire that badly-mauled the Imperial advance. Pappenheim himself was killed. However, the Imperials, particularly the cavalry, fought on ferociously, and slowly managed to push the Swedes back to the road. Gustavus swiftly rallied his cavalry and charged the Imperials, taking some pressure off his infantry and allowing them to dig in in defensive positions along the road.
Around 13:00, Gustavus was shot and killed. Word rapidly spread, and it is a testament to the superb training and discipline of the Swedes that they did not rout at this point. Bernhard Saxe-Weimar assumed command, and encouraged his men to avenge their fallen king. A ferocious assault was launched on the Imperial centre, which swung back and forth for hours before the Swedes were finally successful. By the time Pappenheim’s infantry arrived, both sides had lost close to 6,000 men, and with the sun setting, Wallenstein believed the situation was hopeless and withdrew his army to Leipzig.
Gustavus’ intervention ensured the survival of a Protestant northern Germany. Less esoterically, his revolutionary new concepts of lightweight mobile artillery, mobile infantry units, linear tactics, and outmanoeuvring the enemy on the battlefield swiftly became part of nearly every army’s doctrine and endure to this day. Frederick the Great, Napoleon and Clausewitz all considered him to be among one of the greatest commanders who ever lived. Breitenfeld is still studied at the United States Military Academy as an example of a decisive victory. The Lion of the North truly earned his sobriquet, as well as the dedication to him on the memorial stone that still stands at Breitenfeld:
Freedom of Belief for the World, salvaged at Breitenfeld, Gustav Adolf, Christian and Hero. 7 September 1631