Story highlights Republicans emerge as an anti-slavery party in 1800s

Abraham Lincoln was party's first president

GOP got name Grand Old Party from a Chicago newspaper

Some may not realize that the modern Republican Party owes its origin to the fight over slavery nearly two centuries ago.

In the tumultuous mid-1800s, right before the Civil War, some political activists were concerned about keeping slavery from spreading into new western territories, and they saw no way to stop it through existing political powers: the Democrats and the Whigs (the pro-Congress party of the mid 1800s that largely destroyed itself in the 1852 elections in a battle over slavery).

So they formed a new party, taking the name "Republicans" in a salute to earlier American politicians.

By 1861, they had their first president: Abraham Lincoln. Soon after, slavery fell. The Whig party disappeared. And the Republicans began a long steady rise in power.

Even back then, the party liked to talk about fiscal responsibility -- immigration, religion -- and the need for a strong business climate. All of this spurred a sympathetic Chicago newspaper to call the Republicans the Grand Old Party, or the GOP.

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Republican voters were strongest in rural and western parts of the country, and they were highly successful at maximizing electoral votes to produce presidents: Ulysses S. Grant and Theodore Roosevelt were among their early successes.

However, World War I brought sharp policy disagreements to the party. And when Herbert Hoover ushered in the Great Depression, the Republicans were driven into retreat.

It would be 20 years until they won the White House again, under Dwight Eisenhower.

But since 1969, they have been largely back to their winning ways.

During that time, Republicans have been in the Oval Office for almost twice as many years as the Democrats -- Nixon (elected to two terms, but resigned at the start of his second), Ford (served out Nixon's second term), Reagan (elected to two terms), George H.W. Bush (elected to one term) and George W. Bush (elected to two terms).

Now Mitt Romney is hoping to restart that tradition.