Denmark had been forced out of the Great Northern War by the treaty of Traventhal in 1700, but had long planned on reopening hostilities with the goal of reconquering the lost provinces Scania, Halland and Blekinge. After the Swedish defeat at Poltava in 1709, the Danes saw an opportunity and declared war on Sweden the same year. The declaration of war arrived at the Swedish state council on October 18, 1709. The pretext given were that Sweden had been cheating with the Sound Dues, and that the population of Scania, Halland, Blekinge and Bohuslän had been mistreated.
In late fall 1709, an enormous Danish fleet gathered in Øresund, and on November 2 it arrived at Råå. The Danish invasion army was led by general Christian Ditlev Reventlow and consisted of 15,000 men divided into six cavalry regiments, four dragoon regiments, eight infantry regiments and six artillery companies. It was met with virtually no resistance from the Swedes. The Swedish army was in terrible shape after Poltava, when several regiments had been completely annihilated. The work on reconstructing and recruiting the regiments had begun immediately after Poltava, but by late summer 1709, Magnus Stenbock only had one Scanian regiment in battle-fit condition. The Swedish counterattack would have to wait and the army retreated into Småland. In the beginning of December, the Danes controlled almost all of central Scania except for Landskrona and Malmö. Their objective was to take the naval base at Karlskrona in Blekinge, and the Danish army worked its way quickly into Sweden. In January 1710, it defeated a smaller Swedish force outside Kristianstad.
Stenbock had frantically tried to gather a new Swedish army and several new regiments had begun to assemble in Växjö, from where Stenbock had planned to march. The raw recruits were exercised daily on the ice of a frozen lake close to the city. By February 5 Stenbock had moved to Osby where additional units joined in. By now, about 16,000 men were part of his host. Helsingborg was the key to Scania and Stenbock intended on marching over Rönneå to Kävlingeån, in doing so cutting off the Danish supply lines.
The Danish commander Reventlow saw the threat and turned immediately to meet the Swedes, but when they reached Ringsjön in central Skåne, Reventlow was suddenly taken ill and had to yield command to lieutenant-general Jørgen Rantzau. Rantzau feared being wedged between the Swedish army and the Swedish garrison in Malmö and therefore moved towards Helsingborg. Once in the city, Rantzau could be reinforced and when he camped his force amounted to 10,000 foot soldiers and 4,000 horsemen. Stenbock received the news of the Danish march too late and had to race to Helsingborg. The night of February 28, he camped northeast of the city. The Swedish army was at the time as large as the Danish army, with more cavalry and fewer infantry.
On the morning of February 28 Stenbock marched south towards Helsingborg. When he approached the Danish positions he ordered his army to take battle positions. A thick morning fog lay over the area and hid the two parties from each other. When the fog lifted the two commanders could review over their respective armies. Rantzau saw that the Swedish army outflanked his own left flank in the west and was forced to reinforce it quickly. Rantzau had deployed his artillery on the heights of Ringstorp, from where he started firing at the Swedish troops at noon.
Instead of profiting from the weak Danish west flank Stenbock turned his army eastward to the Danish right flank. This was perceived by the Danes as an attempt to encircle their eastern flank, and to prevent this they marched further east, opening up gaps in the Danish line that couldn't be filled. In the east, by Brohuset, the first skirmishes took place. The Swedes were repelled and Swedish commander Burenskiöld was captured. However, the rest of the Swedish east flank was able to improve the situation and soon the Danes were at a disadvantage. Rantzau participated in the fighting personally, not thinking of the direction of the battle, and was eventually wounded by a bullet through the lung. At the same time a rumor developed in the Danish east flank that the Swedes had encircled them and were attacking from behind, which caused the entire formation to collapse with the troops fleeing towards Helsingborg.
Rantzau's disappearance from the field became noticeable in the middle of the Danish line where the Swedish forces had begun to attack. The Danes had great difficulties withstanding the assault, and when the troops saw how the eastern flank was faring, the middle started to collapse. The Danish elite forces Gardet and the corps of grenadiers which were deployed on the edges could prevent the Swedish advance long enough to allow the other forces to pull back, but many of the fleeing troops were cut down by the Swedish cavalry.
Now the Swedes attacked the gap that had formed between the Danish center and its western flank. Here too the Danes had no leadership, since the commander von Dewitz had been ordered to the eastern side of battle. The Swedish cavalry chased off the Danes and thus surrounding the grenadiers. The other elite force, Gardet, had already been forced to retire and the situation became untenable for the Danes. Major general Valentin von Eickstedt ordered the Danish retreat.
The remainder of the Danish army had sought refuge within the walls of Helsingborg, and Stenbock avoided attacking them as they had too advantageous a position. Instead he besieged the city and invited the Danes to capitulate, but the offer was dismissed by von Dewitz. A Swedish council of war determined that Swedish forces were too weak to storm the city, and instead started a bombardment of the city. By March 5 the last remains of the Danish army left Scania after slaughtering all their horses and sabotaging their cannons.
The Danes lost over 7,500 men, who had been either killed, wounded, or captured. The Swedish losses amounted to 2,800 dead or wounded. The Danish army left Scania, never to return again.
The city of Helsingborg was hit hard by the battle, due both to the Swedish bombardment which destroyed its buildings, and all the remaining human and horse cadavers poisoned the wells. A plague epidemic then harrowed the town and further reduced its population. Helsingborg did not recover until the middle of the 19th century.