Records of kings, emperors, saints and other famous historical figures are often obscured by bias, idealization, and apotheosis. The figures best traits (or sometimes their worst) are exemplified in both text and art to express a specific image for later generations, but very rarely have these sources shown accurate portrayals of historical people. There are other methods, however, to see what figures actually looked like.
Since antiquity people have created death masks, plaster molds of the deceased's face. These masks are perfect renditions of an individual intended to be kept by loved ones to cherish, display, and venerate. In recent years new technology and methodology has allowed us to have an even better glimpse of the past. Anthropologists, forensic scientists, and CGI artists have used their combined knowledge and skills to make facial reconstructions of historical figures. These practitioners use skeletal remains to recreate human faces. This is done by generating a 3D model of a human skull through CT scan, then using tissue data or relevant historical data, including known diet and lifestyle, to fill out the soft tissue. It's become a popular method of recreating the past, but since its introduction, the method has been scrutinized by audiences for what they believed were artistic liberties. Certain figures like Egyptian Queen Nefertiti or the 10,000 year-old "Cheddar Man" from Somerset, England were criticized for having a different skin color than people expected, while the 9,000 year old Greek Avgi received criticism for looking angry.
CGI reconstructions may not be the most realistic (or sometimes the most satisfying) renditions of these historical figures because granted they are a both science and art, but as of yet, they are the best insight to know what famous historical figures really looked like.