Shaka Zulu

So Shaka Zulu had a really hard time getting over the death of his mother:

Shaka had made enough enemies among his own people to hasten his demise. It came relatively quickly after the devastation caused by Shaka's erratic behavior after the death of his mother Nandi. According to Donald Morris in this mourning period Shaka ordered that no crops should be planted during the following year, no milk (the basis of the Zulu diet at the time) was to be used, and any woman who became pregnant was to be killed along with her husband. At least 7,000 people who were deemed to be insufficiently grief-stricken were executed, though it wasn't restricted to humans, cows were slaughtered so that their calves would know what losing a mother felt like. (ref: wikipedia)