President Moon Jae-in declared the Games open and watched as South Korea's 2010 Olympic gold medallist, Kim Yuna, lit the Olympic cauldron which will burn throughout the Games.
U.S. President Donald Trump and Supreme Leader of North Korea Kim Jong Un were not among those present.
Kim's unusual invitation, which was received by Moon with both caution and optimism, was the latest sign of growing closeness between the two rival governments after an exceptionally tense period over the North's nuclear weapons program. During the ceremony, the image of a dove lit up the sky.
North Korean cheerleaders cheer the unified Korean team ahead of its women's preliminary round ice hockey game against Switzerland in Gangneung, South Korea, at the Pyeongchang Winter Olympics, Feb. 10, 2018.
Riyadh Ritz-Carlton corruption purge Saudi hotel reopens
At the end of January the Saudi prosecutor general's office said more than $100bn (£72bn) had been recovered. The iconic hotel is also where President Donald Trump stayed during his May visit to the kingdom.
Internet problems before and during the opening ceremony of the Winter Olympics on Friday night are being investigated as a possible cyberattack, officials said Saturday.
It's important not to overestimate the significance of all this.
The sentiments about North Korea's participation in the South Korea-hosted Winter Games are not being shared across the political spectrum. Last week, the United States said it would ramp up sanctions.
Kim Yo-jong and the North's honorary president, Kim Yong-nam, who officially led the delegation, were seen sitting next to the South Korean president on Sunday during the North Korean Samjiyon Orchestra's second concert at the National Theatre of Korea in Seoul.
A sudden diplomatic breakthrough between North Korea and the United States seems hardly more likely than when Kim started what some are derisively calling his "charm offensive", and it's important Kim not be allowed to weaken ties between South Korea and the United States.