Winter solstice

Source: Google

Popularly known as 冬至 among the Chinese community. Legend has it that the birth date of Jesus was moved to 25th December to coincide with winter solstice - the shortest day, after which the sun was "reborn" and daylight hours become longer.

The marking of 冬至 as a holiday was recorded as far back as the Spring-Autumn (春秋) Period (722-481 BC). The Book of Later Han (后汉书) records, "冬至前后，君子安身静体，百官绝事，不听政，择吉辰而后省事." Roughly translated as, "the time around 冬至, the emperor rested and calmed his body, the imperial palace refused to work, the imperial sessions ceased, auspicious dates were selected."

So the concept of "clear leave" is not that modern after all. However, unlike modern workaholics, the annual leave was mandated and presumably enforced. Imagine being forced to go on leave on the pain of death or torture, or bosses being put under the guillotine for not letting staff go on leave!