Starbucks stores across South Korea will close for half a day next week for staff to attend a history lesson following a promotional campaign gone awry, the coffee giant said on Monday.

Starbucks Korea, with more than 2,000 stores nationwide, found itself embroiled in public uproar last month when it ran a “Tank Day” promotion evoking a deadly military crackdown on a 1980 pro-democracy uprising.

The day of the reusable cup promotion – May 18 – coincided with the 46th anniversary of the Gwangju uprising in which 165 civilians were killed, according to the official toll, though many believe the real figure to be much higher.

South Korea is the company’s third largest market after the United States and China.

Shinsegae Group, which operates Starbucks under a licensing agreement, fired its South Korea chief executive the very day news of the scandal broke, and apologised.