Invasions Over Frozen Seas

Occasionally Mother Nature has lent her hand to invading armies (or conspired against those being invaded, depending on your point of view). Several such events involved Swedish armies marching across a frozen Baltic Sea against northern European adversaries.

These armed conflicts were long after the Vikings used the same open seas to travel to Europe, the Middle East and out to the North Atlantic – before there was a Sweden as we know it today.

For most of the 13^th to the 16^th centuries, economic control in Northern Europe was wielded by a federation of cities around the southern coasts of the Baltic and North Seas known as the Hanseatic League. It began with the emergence of powerful rulers in northern Germany who expanded trade among many merchant-oriented cities in the region from Novgorod in the east to London in the west. Shipping was aided by the waters of the Baltic Sea being mostly open year-round, at least into the 1400s.

 

The spread of the Hanseatic League in 1400 (retrieved 17 February 2020 from https://commons.wikimedia.org/wiki/File:Ausbreitung_der_Hanse_um_das_Jahr_1400-Droysens_28.jpg)

Beginning in the 15^th century, climate conspired to cause cold weather, drought, poor harvests and famine; plague attacked populations across Europe; the rivers and seas began to freeze over more frequently. Communication and trade were impacted by both population reduction and increasing conflict among powers outside the Hanseatic League who were facing their own economic hardships.

During the Little Ice Age, the Baltic Sea was covered in ice in most years, entirely frozen solid during a few, allowing easy passage from Scandinavia to continental Europe. One of the emerging power centres was the Swedish Empire. In search, no doubt, of lands that could produce more food and economic benefit, it expanded its reach around the Baltic, often through armed invasion. Following the end of the 30-year War (1618-48), Sweden controlled much of the region, from Russia to Denmark.

 

Map of the Swedish Empire (retrieved 17 February 2020 from https://commons.wikimedia.org/wiki/File:Sweden_1658.jpg)

Invasions of Europe by Sweden during the 16^th and 17^th centuries were aided by the frozen conditions of the Baltic Sea. During the Northern Wars (1655-60), Swedish troops marched right across the ice-covered Great Belt and Little Belt straits, into Denmark and Germany.

 

Depiction of Charles X Gustav looking over the ice of the Great Belt as Swedish forces march across the Belt Straits 1657-58 (retrieved 17 February 2020 from https://commons.wikimedia.org/wiki/File:T%C3%A5get_%C3%B6ver_stora_b%C3%A4lt.jpg)

The tables were turned on the Swedes in 1678. Frederick William, elector of Brandenburg and Duke of Prussia, had defeated the Swedish army at the Battle of Fehrbellin in 1675, after an attempted invasion. He further drove them from the Duchy by commandeering thousands of sleighs to transport his army across snowy terrain and frozen lakes and rivers. They were able to cut into the flanks of the Swedish forces, denying them the ability to resupply. The battle would be a precursor to a modern-day motorized infantry.

 

Frederick William the Great pursues Swedish troops across the frozen Curonian Lagoon; fresco by Wilhelm Simmler, ca. 1891; artwork was destroyed by bombing in 1944 (retrieved 17 February 2020 from https://commons.wikimedia.org/wiki/File:%C3%9Cbergang_%C3%BCber_das_Kurische_Haff_1679.jpg)

Conditions of the Little Ice Age caused deprivation and death on a widespread basis across Europe. They also resulted in many nations looking outside their boundaries for better conditions or more food sources. In some cases, trade was increased; in others, wars were fought. Frozen rivers, lakes and seas made it easier for armies to advance against their foes.