WASHINGTON — As New Year’s Day approached 150 years ago, all eyes were on President Abraham Lincoln in expectation of what he warned 100 days earlier would be coming — his final proclamation declaring all slaves in states rebelling against the Union to be “forever free.”

A tradition began Dec. 31, 1862, as many black churches held Watch Night services, awaiting word that Lincoln’s Emancipation Proclamation would take effect amid a bloody Civil War. Later, congregations listened as the president’s historic words were read aloud.

The proclamation would not end slavery outright and at the time couldn’t be enforced by Lincoln in areas under Confederate control. But the president made clear from that day forward that his forces would be fighting to bring the Union back together without the institution of slavery.

Lincoln issued his preliminary Emancipation Proclamation in September 1862, after the Battle of Antietam, announcing that if rebel states did not cease fighting and rejoin the Union by Jan. 1, 1863, all slaves in rebellious states or parts of states would be declared free from that date forward.

This year, the Watch Night tradition will follow the historic document to its home at the National Archives with a special midnight display planned with readings, songs and bell ringing among the nation’s founding documents.

The official document bears Lincoln’s signature and the United States seal, setting it apart from copies and drafts. It will make a rare public appearance from today to Tuesday — New Year’s Day — for thousands of visitors to mark its anniversary. On New Year’s Eve, the display will remain open past midnight as 2013 arrives.

“We will be calling back to an old tradition,” said U.S. Archivist David Ferriero, noting the proclamation’s legacy. “When you see thousands of people waiting in line in the dark and cold ... we know that they’re not there just for words on paper.

“On this 150th anniversary, we recall those who struggled with slavery in this country, the hope that sustained them and the inspiration the Emancipation Proclamation has given to those who seek justice.”

The National Archives allows 100 visitors at a time into its rotunda, where the Emancipation Proclamation will be displayed along with the Constitution and Declaration of Independence. On the busiest days, 8,000 people file through for a glimpse of the founding charters.

Performances and re-enactments are scheduled to continue throughout New Year’s Day. The U.S. Postal Service will unveil a new Emancipation Proclamation stamp as well.

This special display is just one of many commemorations planned in Washington and in churches nationwide to mark the anniversary of Lincoln’s actions to end slavery and end the Civil War.

President Lincoln’s Cottage in Washington, where the 16th president spent much of his time and where he began drafting the proclamation, is displaying a signed copy of the document through February. It also will host its own New Year’s Eve celebration.  

The Library of Congress will display the first draft handwritten by Lincoln. It will be on display for six weeks beginning Jan. 3 in the library’s exhibit, “The Civil War in America,” which features many personal letters and diaries from the era.

Also, the Smithsonian’s National Museum of African American History and Culture just opened its newest exhibition, “Changing America,” to recount the 1863 emancipation of slaves and the 1963 March on Washington for Civil Rights. It includes a rare signed copy of the 13th Amendment to the Constitution that ultimately abolished slavery.

The Watch Night tradition also continues at many sites Monday night.

In Washington, the Metropolitan A.M.E. Church, where abolitionist Frederick Douglass was a member, will host a special 150th anniversary service.

History lovers say this is a chance to remember what the Emancipation Proclamation actually signified.

Lincoln wrote in part: “I do order and declare that all persons held as slaves within said designated States, and parts of States, are, and henceforward, shall be free.”

He went on to say the military would recognize the freedom of slaves, that freed slaves should avoid violence and that freed slaves could enlist in the U.S. armed forces. It did not immediately free a single slave, though, because Lincoln didn’t have the power to enforce the declaration in the Confederacy. Still, many slaves had already been freeing themselves, and the document gave them protection, said Reginald Washington, an archivist of African-American history at the National Archives.

“It was a first, important step in paving the way for the abolishment of slavery with the ratification of the 13th Amendment,” he said.

It also brought “a fundamental change in the character of the war,” Washington said. “With the stroke of Lincoln’s pen, a war to preserve the union had overnight become a war of human liberation.”

The proclamation became a symbol of hope for nearly 4 million slaves and a confirmation that the war should be fought to secure their freedom, said Washington, who is retiring from the Archives after nearly 40 years. Some historians and scholars have come to view to proclamation as one of the most important documents in U.S. history.

The final proclamation has been rarely shown because it was badly damaged decades ago by long exposure to light. After it was signed at the White House, it was kept at the State Department for many years with other presidential proclamations. In 1936, it was transferred to the National Archives.

Records show it was displayed between 1947 and 1949 in a “Freedom Train” exhibit that traveled the country. Then it was shown briefly in January 1963 to mark the 100th anniversary of its signing.

It wasn’t until 1993 that the Emancipation Proclamation has been shown more regularly to the public. In the past decade, it has been shown in 10 other museums and libraries nationwide for no more than three days at a time to limit its exposure to light. A 2011 exhibition at the Henry Ford Museum in Dearborn, Mich., that was open around the clock drew lines amounting to eight-hour waits to see the document.

Conservators rotate which of the five pages are shown to limit their light exposure. In Washington, they will display pages two and five, which is Lincoln’s signature page. High-quality copies are shown in place of the other original pages.

“It’s rarely shown, and that’s part of our strategy for preserving it and making it accessible,” said Catherine Nicholson, an archives conservator. “Our goal is to keep its current condition so that it can be enjoyed not only by people today, but by future generations.”