Political History

http://en.wikipedia.org/wiki/Left-Right_politics

Additionally, the terms "liberal" and "conservative," in a strictly political sense, date to about 50 years later. In 1819, there was a massacre of workers at St. Peters Fields near Manchester, and it became known as the "Peterloo" massacre, which was an ironic naming, as the battle of Waterloo had taken place just four years earlier, and the Duke of Wellington, the victor at Waterloo, was a notorious Tory (we would say conservative) and was already on record as opposing organized labor and electoral reform.

Peterloo made many people uncomfortable who had previously opposed electoral reform, or who had at least not supported it. The seats in the House of Commons were riddled with members sitting for "rotten boroughs" (meaning a borough which had once had a large population, but now did not, so that therefore a handful of men elected a member of Parliament) and with "pocket boroughs" (this meant a borough, nearly the entire or actually the entire property of which was owned by a single man, and the electors of the borough were all the tenants of this man, who therefore had the borough "in his pocket"). The worst example was Old Sarum, all of the property of which was owned by absentees, with the exception of some very small holdings which did not qualify their owners to vote. Just eleven men elected the two members of Parliament for Old Sarum, and they all the lived somewhere else. It was the "poster child" for rotten boroughs.

This increasingly made people uncomfortable, especially after the events of the French Revolution, and the Wars of the Revolution and the Napoleonic Wars. It seemed to many people that England had fought to end the tyranny of Napoleon, who they viewed with as much horror as their descendants would view Hitler. Most of the members of the army were men who were very, very poor, or who could not escape being pressed for service, or pay a bounty for someone else to take their place. English officers commonly called them "the scum of the earth," and Wellington is one of those who was alleged to have said that.

The lowest order of the electors (i.e., those with the least property, who just managed to qualify) took up the cause of the working class. Many of them were but recently risen from the same class. Members of the middle class, many of whom were evangelical Christians, and many of whom had supported Wilberforce's movement to end slavery and the slave trade, were increasingly uncomfortable with a "rotten" Parliament, and those who had opposed electoral reform now kept silent, while others who had previously taken no position, began to favor electoral reform.

The term liberal comes from a Latin word meaning a free man, or a freed man (a former slave who had been manumitted)--think of the word liberate. The term had usually meant generous both in spirit and in fact, and those who now came to support electoral reform and the rights of labor to organize became known as liberals. Those who resisted change came to be known as conservatives, as wanting to preserve the old order. The terms began to be used in newspapers in the early 1830s, at the time that the first Reform Bill was being battled over furiously in Parliament.

Therefore, at the time of the Reform Bill, Tories were increasingly referred to as Conservatives, and Whigs were increasingly referred to as Liberals. It wouldn't do to delve any further into the matter, since most subsequent reform was carried out by Peelite and Canningite Tories (conservatives, who were the supporters of either Robert Peel--he founded the Metropolitan Police, which is why they are called "Bobbies"--or of George Canning), while Lord Palmerston joined the Liberals and Lord Grey, although he had previously opposed electoral reform. After he became Prime Minister for the second time in 1859, he said that there would be further electoral reform only over his dead body. That was literally true, as no new reform bill was introduced until after his death in 1865.

To cloud matters further, the original party founded by Thomas Jefferson, and from the wreck of which Andrew Jackson built the Democratic Party, was the Democratic-Republican Party, and they were generally just referred to as the Republicans.