Clocks show time in Seoul, left, and Pyongyang at the Peace House in the demilitarized zone in the border village of Panmunjom between North and South Korea on April 25. (Cheong Wa Dae/South Korean Presidential Office)

On Aug. 15, 2015, North Koreans put their clocks back half an hour to establish their own time zone, “Pyongyang time.” Less than three years later, the country put their clocks forward half an hour so they are again in the same time zone as South Korea.

It's a symbolic but still noteworthy move. North Korean leader Kim Jong Un had apparently decided to standardize his country's time zone with South Korea when he visited the demilitarized zone to meet Moon Jae-in, the South Korean president, last week for a historic summit.

According to a dispatch from state-run Korea Central News Agency (KCNA), Kim had seen two clocks on the wall that showed two separate times for the Koreas. “It was a painful wrench to see two clocks indicating Pyongyang and Seoul times hanging on a wall of the summit venue,” Kim was quoted as saying by the news service.

He then pledged to change North Korea's time zone back to how it was before.


This graphic shows time zones in 2015, after North Korea changed to “Pyongyang time.”

It's quite a change in tone from 2015, when KCNA announced the time zone change. At the time, the news agency had reported that North Korea could no longer stand to be in a time zone that was set under Japanese occupation.

“The wicked Japanese imperialists committed such unpardonable crimes as depriving Korea of even its standard time while mercilessly trampling down its land,” KCNA wrote  in its typical house style.

There was some historical truth to North Korea's complaints. Korea had only briefly set its clocks to a half-past time zone before being occupied by Japan in 1910, which then implemented its own time zone in Korea. South Korea returned to the older time zone in 1954 but shifted to the Japanese time zone in 1961, in part due to concerns about logistics for U.S. troops stationed in Japan.

A look at a map would have also suggested some scientific logic. North Korea sits midway between Japan and China, so why wouldn't it have a time zone between them?

In truth, however, North Korea's time zone was like most others: arbitrary. China and India, for example, both have only one time zone across their vast countries, creating parts of the country where the mornings stay dark and the evenings are light. Russia, meanwhile, has 12 time zones and has changed them multiple times in recent years.

North Korea wasn't the only country to have a time zone that was at half an hour past the coordinated universal time. Under Hugo Chávez, Venezuela changed its time zone to half past the hour in 2007; India and Iran were already using time zones that didn't match to the nearest hour. Nepal uses a time zone that is 45 minutes past the hour.

The 2015 decision to change the time zone appeared to be grounded neither in history nor logic but instead was a symbol of deteriorating inter-Korean relations.

Missile tests had strained relations between Seoul and Pyongyang over the previous few years and, after an incident that saw South Korean border guards maimed by a mine in the demilitarized zone, there was an exchange of artillery fire over the border only a few days after the clocks changed.

The time zone change didn't have major practical impact on relations, but it did cause some confusion at the Kaesong industrial zone in North Korea, where South Korean companies employed North Korean workers in a rare attempt at economic cooperation.

Notably, Kaesong closed a few months later after another bout of tension on the peninsula.

Times change, of course. After the inter-Korea summit last week and with hopes high for a U.S.-Korea summit soon, there's lots of optimism on the peninsula. If sanctions on North Korea are lifted, Kaesong may eventually reopen; there's even discussion of a joint rail network that could connect the two nations for the movement of goods and people.

For now, the two Koreas are on the same page, and the hope is that if they are looking at the same clock, things can progress faster. As KCNA put it Friday, changing clocks would “speed up the process for the north and the south to become one and turn their different and separated things into the same and single ones.”

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