The World Cup regulars have not been crowned Asian champions since 1960, and they made an ill-disciplined start with both Yong-woo Park and Min-jae Kim booked inside 12 minutes.
Bahrain were frustrating Jurgen Klinsmann’s South Korea at that point, but the Taegeuk Warriors gradually grew in the first half and took the lead on 38 minutes when Jae-sung Lee squared and In-beom Hwang checked back to curl the ball into the top-left corner.
South Korea started the second half well but were caught napping and conceded a shock leveller when Abdullah Al Hashash tapped home from close range.
But while it was a bit of an off day for captain Heung-min Son, PSG’s Lee began to assert his dominance on the match — and it was his quality in the final third that brought South Korea their reward.
Just five minutes after Bahrain had equalised, Lee fired a powerful curling effort into the bottom-left corner which nicked the post on the way in. It was a stunning goal which restored South Korea’s lead.
Bahrain had huffed and puffed but they faded as the contest wore on, and Son won the ball in midfield before beginning an attack which ended with Lee’s second of the afternoon.
The 22-year-old received the ball on the left with no one near him for company. He checked back onto his left foot and passed the ball calmly into the corner.
Lee continued to run the show, and Son missed a number of presentable chances as South Korea created opportunities to further extend the scoreline late on.
The Spurs skipper was then booked in stoppage time for a needless dive, but his nation had done enough for victory here and go top of Group E ahead of Malaysia and Jordan facing off later on.