The Forgotten War – The 3 Key Causes of the Anglo-American War of 1812

In this introduction to history that follows a piece on the American Revolution, Aidan Curran explores the reasons for the War of 1812. And he finds that there are three principal reasons for the war that broke out between Britain and the US.


Never heard of the War of 1812? Well, you are not alone. This war is often called the “Forgotten War,” as it is overshadowed by other conflicts in American history such as the American Revolution and the American Civil War. However, this is a significant event in American history as it was the first time that the United States declared war on another country. And guess who they declared war on? Yes, you guessed it – Britain. Even after the war of independence, it seems the British still wanted to stick their noses into American affairs, by impeding trade and taking men off American ships whom they believed were British.

This article is going to examine the three main causes of this “Second War of Independence,” – trade, impressment (kidnapping), and expansion.

The Forgotten War – The 3 Key Causes of the Anglo-American War of 1812

US Frigate Constitution defeats the British Frigate Java in December 1812.

1. Trade      

In 1803, Britain was locked in a conflict with Napoleon’s France. In order to win this war, Britain had to cut off all supplies to France. This meant interfering with American shipping, and as you can imagine, the Americans were not too happy about this. According to international law, neutral countries could trade with whoever they wished, as long as they traded non-military goods.  Americans felt that their rights as a free nation were being violated, and introduced a number of restrictive trade measures, such as embargoes, in order to preserve the economic health of the United States. This could be called a cold war, as these trade restrictions were made in an effort to avoid full on, bloody war. James Madison, the fourth President of the United States, once exclaimed “What a noble stroke would be an embargo! It would probably do as much good as harm at home, and would force peace on the rest of the world, and perhaps liberty along with it.”

So in December 1807, Congress passed the Embargo, which banned all American ships sailing to foreign ports. In 1808, American exports plummeted by 80%. However, this Embargo Act had little effect on Britain. In all honesty, she couldn’t care less; the British were far more interested and consumed in their battle with the French. In fact, the only people who suffered were the Americans, as the economies of port cities suffered. Exports fell from $108 million in 1807 to $22 million in 1808, and imports fell from $138 million to less than $57 million. To say the Embargo Act backfired would be an understatement – it was an absolute disaster! The Non-Intercourse Act was introduced instead, which banned trade only with Britain and France, who were still locked in combat. To win this war, Britain saw it as necessary to “kidnap” sailors from American ships in order to increase manpower, which brings us on to the next cause of the War of 1812.


2. Impressment

If there was one thing in particulr that annoyed the Americans, it was impressment. This was when the British would board American ships, and take sailors they believed to be British citizens. Granted, many were, but many had also become naturalised Americans. Between 1793 and 1812, the British impressed more than 15,000 US sailors in an effort to boost fleet numbers in their war with France.

The process of impressment started back in 1664, as the Royal Navy organised gangs to roam the countryside, forcing British subjects to join. By the 18th century, these gangs were boarding neutral merchant ships to kidnap men to serve in the navy.

Americans regarded the practice of impressment as a violation of a person’s liberty, as stated in the Declaration of Independence. So when the British started boarding American ships and taking men, this was obviously going to cause considerable tensions.

Why were so many British men working on American ships? Simply put, American ships offered better pay and working conditions. It is estimated that 35 to 40 per cent of US naval crews were made up of British seamen in the nineteenth century, often deserters of the Royal Navy. Many of these had become naturalised Americans, but in British eyes, no subject could ever renounce their citizenship. The Americans conceded the right of the British to impress their own subjects from American ships. However, when legally naturalised Americans were taken, this was a cause of huge irritation. And when US-born people were impressed, this caused even greater tension. Between 1803 and 1812, at least 5,000 sailors were snatched from American ships and forced to serve in the Royal Navy, and it is estimated that three out of every four were Americans.

The most controversial case of impressment occurred in Virginia on June 22, 1807. A British warship called the HMS Leopard opened fire on an American ship called the USS Chesapeake. The British boarded the ship, looking for deserters from the Royal Navy. They found and impressed four men, but only one was an actual British citizen. The incident outraged the American public, with President Thomas Jefferson remarking: “Never since the Battle of Lexington have I seen this country in such a state of exasperation as at present, and even that did not produce such unanimity.” War was looming ever closer…


3. Expansion

American expansionism can also be cited as a cause of the War of 1812, as the country tried to extend its influence to the north-west, in places such as Illinois, Indiana, and Michigan. As the Americans tried to expand, they faced fierce resistance from Native Americans, who wanted to keep their land from the colonists, reform their habits, and establish a confederacy on American soil.

But what has this got to do with the British? Well, the British began to give support to the Native Americans by providing arms and supplies. They saw the Native American Nations as being valuable allies, while also hoping that a Native American buffer state would be formed, which would halt American growth and expansion, and ensure that Canada remained a British possession. In the Battle of Tippecanoe in 1811, the defeated Native Americans left behind rifles of British manufacture on the battlefield. This confirmed to the Americans that the British were up to no good, and along with trade interference and impressment, it seemed that the only option was to go to war, and that’s exactly what they did.  On June 1, 1812, President James Maddison gave a speech to the US Congress, in which he described American grievances against the British. The war officially began on June 18, as President Maddison signed the measure into law. This was the first time America had ever declared war on another country.


To sum it all up

The fundamental cause of the War of 1812 between America and Britain is pretty straightforward – both sides could not agree on what was theirs. The British believed that no person could renounce their citizenship, while Americans recognised legally naturalised citizens. This led to a disagreement over impressment, and who exactly was British and American. Sometimes, the British did not even care, and took whoever they wanted off ships, including Americans. This angered the Americans, as their freedom was being violated. On trade, Americans believed that as a neutral country, they should be able to exchange goods with whoever they wanted. Again, there was dispute over this, as the British disagreed. Finally, greed was also a major cause of war, as America wanted to expand its territory, but Britain did not want this, in fear of losing Canada.

America and Britain were like two children in a sweet shop, stealing each other’s sweets and arguing over which sweets were theirs, while also looking to expand their number of sweets! If only they had learned to get along…


You can find out more from Aidan Curran on his site here or his Twitter feed here.


Finally, read more about an adventure from the War of 1812 in issue 4 of History is Now magazine here.

The Forgotten War – The 3 Key Causes of the Anglo-American War of 1812


  • Eric Foner, Give Me Liberty!
  • John Garraty, Short History of the American Nation
  • Maldwyn Jones, The Limits of Liberty
  • Bradford Perkins.  Embargo: Alternative to War 
  • John P. Foley, The Jeffersonian Cyclopedia.
  • Samuel Eliot Morison, A Concise History of the American Republic